Fix ddev tests when running on release branches (#20151)

* Fix ddev tests when running on release branches

* Add fetch-depth to CI validations

* Remove flag to run Test Agent on any branch to allow CI validation to pass

* Remove extra fetch-depth parameter in ddev

* Remove unused flag from test-all.yaml

* Update fetch master to do it always except on master

---------

Co-authored-by: Kyle-Neale <kyle.neale@datadoghq.com>

Author: AAraKKe

.ddev/ci/scripts/ddev/linux/55_fetch_master.sh

@@ -2,8 +2,8 @@
 
 set -ex
 
-# Only required on pull requests
-if [[ $GITHUB_BASE_REF ]]; then
+# Only required on non-master branches
+if [[ "$GITHUB_REF_NAME" != "master" ]]; then
   git fetch origin master:master
 fi
 

.ddev/ci/scripts/ddev/windows/55_fetch_master.bat

@@ -1,4 +1,4 @@
-:: Only required on pull requests
-if defined GITHUB_BASE_REF (
+:: Only required on non-master branches
+if "%GITHUB_REF_NAME%" NEQ "master" (
   git fetch origin master:master
 )