chore(main): release 0.277.0 (#8103)

Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>

Author: release-please[bot]

VERSION

@@ -1 +1 @@
-1.94.0
+1.95.0

src/SpannerClient.php

@@ -117,7 +117,7 @@ class SpannerClient
     use LROTrait;
     use ValidateTrait;
 
-    const VERSION = '1.94.0';
+    const VERSION = '1.95.0';
 
     const FULL_CONTROL_SCOPE = 'https://www.googleapis.com/auth/spanner.data';
     const ADMIN_SCOPE = 'https://www.googleapis.com/auth/spanner.admin';