Update RELEASING.md

Author: loosebazooka

RELEASING.md

@@ -6,4 +6,4 @@ Barebones releasing instructions
 - Tag the new release (at the above commit)
 - Tagging triggers a goreleaser build on github actions
 - Artifacts are automatically added to the github release
-- Container images are published to ghcr.io/googlecontainertools/container-structure-test (:latest, :<version>)
+- Container images are published to ghcr.io/googlecontainertools/container-structure-test (:latest, :\<version\>)