chore: add translate dev team for translate samples (#13013)

Author: iennae

.github/CODEOWNERS

@@ -88,6 +88,7 @@
 /billing/**/*                          @GoogleCloudPlatform/billing-samples-maintainers @GoogleCloudPlatform/python-samples-reviewers @GoogleCloudPlatform/cloud-samples-reviewers
 /video/live-stream/*                   @GoogleCloudPlatform/cloud-media-team @GoogleCloudPlatform/python-samples-reviewers @GoogleCloudPlatform/cloud-samples-reviewers
 /video/stitcher/*                      @GoogleCloudPlatform/cloud-media-team @GoogleCloudPlatform/python-samples-reviewers @GoogleCloudPlatform/cloud-samples-reviewers
+/translate                             @GoogleCloudPlatform/python-samples-reviewers @GoogleCloudPlatform/cloud-samples-reviewers @GoogleCloudPlatform/cloud-ml-translate-dev
 
 # BEGIN - pending clarification
 /memorystore/**/*                      @GoogleCloudPlatform/python-samples-reviewers @GoogleCloudPlatform/cloud-samples-reviewers