Fix typos mostly in comments, docs and test names (GH-15209)

diff --git a/Lib/asyncio/streams.py b/Lib/asyncio/streams.py
index e56e2ef..33b2fa5 100644
--- a/Lib/asyncio/streams.py
+++ b/Lib/asyncio/streams.py
@@ -71,7 +71,7 @@
             ssl_handshake_timeout=None,
             happy_eyeballs_delay=None, interleave=None):
     # Design note:
-    # Don't use decorator approach but exilicit non-async
+    # Don't use decorator approach but explicit non-async
     # function to fail fast and explicitly
     # if passed arguments don't match the function signature
     return _ContextManagerHelper(_connect(host, port, limit,
@@ -442,7 +442,7 @@
                      ssl_handshake_timeout=None):
         """Similar to `connect()` but works with UNIX Domain Sockets."""
         # Design note:
-        # Don't use decorator approach but exilicit non-async
+        # Don't use decorator approach but explicit non-async
         # function to fail fast and explicitly
         # if passed arguments don't match the function signature
         return _ContextManagerHelper(_connect_unix(path,