pick-kotlin-version.py: tolerate warnings

This commit changes pick-kotlin-version.py to use re.search() instead of
re.match(), so that it can better cope with warning messages.

Author: cklin

java/kotlin-extractor/pick-kotlin-version.py

@@ -26,7 +26,7 @@ def version_tuple(v):
 res = subprocess.run([kotlinc, "-version"], text=True, stdout=subprocess.DEVNULL, stderr=subprocess.PIPE)
 if res.returncode != 0:
     raise Exception(f"kotlinc -version failed: {res.stderr}")
-m = re.match(r'.* kotlinc-jvm ([0-9]+\.[0-9]+\.[0-9]+(-[a-zA-Z][a-zA-Z0-9]*)?) .*', res.stderr)
+m = re.search(r' kotlinc-jvm ([0-9]+\.[0-9]+\.[0-9]+(-[a-zA-Z][a-zA-Z0-9]*)?) ', res.stderr)
 if m is None:
     raise Exception(f'Cannot detect version of kotlinc (got {res.stderr})')
 version = m[1]