chore: release 1.27.0 (#704)

Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>
diff --git a/setup.py b/setup.py
index 055fcab..0c30f0b 100644
--- a/setup.py
+++ b/setup.py
@@ -37,7 +37,7 @@
 with io.open("README.rst", "r") as fh:
     long_description = fh.read()
 
-version = "1.26.1"
+version = "1.27.0"
 
 setup(
     name="google-auth",