chore: revert years in manually committed files

.kokoro/build.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
-# Copyright 2021 Google LLC
+# Copyright 2020 Google LLC
 #
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file or at

.kokoro/docker/docs/Dockerfile

@@ -1,4 +1,4 @@
-# Copyright 2021 Google LLC
+# Copyright 2020 Google LLC
 #
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file or at

.kokoro/docker/docs/fetch_gpg_keys.sh

@@ -1,13 +1,13 @@
 #!/bin/bash
-# Copyright 2021 Google LLC
+# Copyright 2020 Google LLC
 #
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file or at
 # https://developers.google.com/open-source/licenses/bsd
 
 # A script to fetch gpg keys with retry.
 # Avoid jinja parsing the file.
-# 
+#
 
 function retry {
     if [[ "${#}" -le 1 ]]; then
@@ -34,4 +34,4 @@ retry 3 gpg --keyserver ha.pool.sks-keyservers.net --recv-keys \
 retry 3 gpg --keyserver ha.pool.sks-keyservers.net --recv-keys \
       E3FF2839C048B25C084DEBE9B26995E310250568
 
-# 
+#

.kokoro/publish-docs.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
-# Copyright 2021 Google LLC
+# Copyright 2020 Google LLC
 #
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file or at

owlbot.py

@@ -17,6 +17,7 @@
 
 # Just move templates for building docs and releases
 # Presubmit and continuous are configured differently
+s.move(templated_files / ".trampolinerc")
 s.move(templated_files / ".kokoro" / "docs")
 s.move(templated_files / ".kokoro" / "release.sh")
 s.move(templated_files / ".kokoro" / "trampoline_v2.sh")