chore(internal/gapicgen): update generator to v0.18.3
Includes a small fix for gapic_metadata generation.
@@ -33,7 +33,7 @@ RUN GO111MODULE=on go get \
golang.org/x/lint/golint@latest \
golang.org/x/tools/cmd/goimports@latest \
honnef.co/go/tools/cmd/staticcheck@latest \
- github.com/googleapis/gapic-generator-go/cmd/protoc-gen-go_gapic@v0.18.2
+ github.com/googleapis/gapic-generator-go/cmd/protoc-gen-go_gapic@v0.18.3
ENV PATH="${PATH}:/root/go/bin"
# Source: http://debuggable.com/posts/disable-strict-host-checking-for-git-clone:49896ff3-0ac0-4263-9703-1eae4834cda3
