build: run docs regen in synth.py (#1059)

diff --git a/docs/dyn/texttospeech_v1.text.html b/docs/dyn/texttospeech_v1.text.html
index 01a7661..596c686 100644
--- a/docs/dyn/texttospeech_v1.text.html
+++ b/docs/dyn/texttospeech_v1.text.html
@@ -95,10 +95,6 @@
     The object takes the form of:
 
 { # The top-level message sent by the client for the `SynthesizeSpeech` method.
-    "input": { # Contains text input to be synthesized. Either `text` or `ssml` must be supplied. Supplying both or neither returns google.rpc.Code.INVALID_ARGUMENT. The input size is limited to 5000 characters. # Required. The Synthesizer requires either plain text or SSML as input.
-      "text": "A String", # The raw text to be synthesized.
-      "ssml": "A String", # The SSML document to be synthesized. The SSML document must be valid and well-formed. Otherwise the RPC will fail and return google.rpc.Code.INVALID_ARGUMENT. For more information, see [SSML](https://cloud.google.com/text-to-speech/docs/ssml).
-    },
     "voice": { # Description of which voice to use for a synthesis request. # Required. The desired voice of the synthesized audio.
       "ssmlGender": "A String", # The preferred gender of the voice. If not set, the service will choose a voice based on the other parameters such as language_code and name. Note that this is only a preference, not requirement; if a voice of the appropriate gender is not available, the synthesizer should substitute a voice with a different gender rather than failing the request.
       "name": "A String", # The name of the voice. If not set, the service will choose a voice based on the other parameters such as language_code and gender.
@@ -106,13 +102,17 @@
     },
     "audioConfig": { # Description of audio data to be synthesized. # Required. The configuration of the synthesized audio.
       "sampleRateHertz": 42, # Optional. The synthesis sample rate (in hertz) for this audio. When this is specified in SynthesizeSpeechRequest, if this is different from the voice's natural sample rate, then the synthesizer will honor this request by converting to the desired sample rate (which might result in worse audio quality), unless the specified sample rate is not supported for the encoding chosen, in which case it will fail the request and return google.rpc.Code.INVALID_ARGUMENT.
-      "audioEncoding": "A String", # Required. The format of the audio byte stream.
-      "pitch": 3.14, # Optional. Input only. Speaking pitch, in the range [-20.0, 20.0]. 20 means increase 20 semitones from the original pitch. -20 means decrease 20 semitones from the original pitch.
-      "speakingRate": 3.14, # Optional. Input only. Speaking rate/speed, in the range [0.25, 4.0]. 1.0 is the normal native speed supported by the specific voice. 2.0 is twice as fast, and 0.5 is half as fast. If unset(0.0), defaults to the native 1.0 speed. Any other values < 0.25 or > 4.0 will return an error.
       "effectsProfileId": [ # Optional. Input only. An identifier which selects 'audio effects' profiles that are applied on (post synthesized) text to speech. Effects are applied on top of each other in the order they are given. See [audio profiles](https://cloud.google.com/text-to-speech/docs/audio-profiles) for current supported profile ids.
         "A String",
       ],
+      "audioEncoding": "A String", # Required. The format of the audio byte stream.
+      "pitch": 3.14, # Optional. Input only. Speaking pitch, in the range [-20.0, 20.0]. 20 means increase 20 semitones from the original pitch. -20 means decrease 20 semitones from the original pitch.
       "volumeGainDb": 3.14, # Optional. Input only. Volume gain (in dB) of the normal native volume supported by the specific voice, in the range [-96.0, 16.0]. If unset, or set to a value of 0.0 (dB), will play at normal native signal amplitude. A value of -6.0 (dB) will play at approximately half the amplitude of the normal native signal amplitude. A value of +6.0 (dB) will play at approximately twice the amplitude of the normal native signal amplitude. Strongly recommend not to exceed +10 (dB) as there's usually no effective increase in loudness for any value greater than that.
+      "speakingRate": 3.14, # Optional. Input only. Speaking rate/speed, in the range [0.25, 4.0]. 1.0 is the normal native speed supported by the specific voice. 2.0 is twice as fast, and 0.5 is half as fast. If unset(0.0), defaults to the native 1.0 speed. Any other values < 0.25 or > 4.0 will return an error.
+    },
+    "input": { # Contains text input to be synthesized. Either `text` or `ssml` must be supplied. Supplying both or neither returns google.rpc.Code.INVALID_ARGUMENT. The input size is limited to 5000 characters. # Required. The Synthesizer requires either plain text or SSML as input.
+      "ssml": "A String", # The SSML document to be synthesized. The SSML document must be valid and well-formed. Otherwise the RPC will fail and return google.rpc.Code.INVALID_ARGUMENT. For more information, see [SSML](https://cloud.google.com/text-to-speech/docs/ssml).
+      "text": "A String", # The raw text to be synthesized.
     },
   }