Update .git and .dockerignore files (#1120)

* Add .git folder to .dockerignore

* noop

* prevent accidentally committing credentials to release artifact

Author: s-westphal

.dockerignore

@@ -14,12 +14,14 @@
 *_pb2.*
 */*_pb2.*
 */*/*_pb2.*
+.git
 ACKNOWLEDGEMENTS
 AUTHORS
 build
 dist
 executables
 !executables/windows/templates/unzipsfx/*.exe
+gha-creds-*.json
 grr/config/grr_response_templates
 grr/gui/static/bower_components
 grr/gui/static/node_modules

.gitignore

@@ -23,3 +23,4 @@ GRRlog.txt
 *.log
 grr/server/grr_response_server/gui/static/third-party
 grr/server/grr_response_server/gui/ui/.angular
+gha-creds-*.json