try -O1 to speed up msan bot

We want it to be a debug build, but it probably doesn't need to be
completely unoptimized.

dm: 27m -> 7m
nanobench: 140m -> 33m

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1678693002

CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Debug-MSAN-Trybot

Review URL: https://codereview.chromium.org/1678693002
diff --git a/gyp/common_conditions.gypi b/gyp/common_conditions.gypi
index 1f90d6f..163f1b4 100644
--- a/gyp/common_conditions.gypi
+++ b/gyp/common_conditions.gypi
@@ -452,7 +452,10 @@
                 'defines': [ 'THREAD_SANITIZER' ],
               }],
               [ 'skia_sanitizer == "memory"', {
-                'cflags': [ '-fsanitize-memory-track-origins' ],
+                'cflags': [
+                    '-O1',
+                    '-fsanitize-memory-track-origins',
+                ],
               }],
             ],
           }],