ignore prettier formatting generated files

Summary: add to ignore

Reviewed By: stbfb

Differential Revision: D85803957

fbshipit-source-id: 721168c8eb68c1217c00bad2742c30af272fd904

Author: evangrayk

addons/.prettierignore

@@ -6,6 +6,7 @@
 /isl-server/dist/
 /isl-server/coverage/
 /isl-server/src/facebook/phabricator/generated/
+/isl-server/src/facebook/fullRepoBranch/generated/
 /isl-server/src/github/generated/
 /vscode/coverage/
 /vscode/dist/