Add dependabot auto-merger (#52)

.github/workflows/dependabot-reviewer.yml

@@ -0,0 +1,11 @@
+name: Dependabot reviewer
+on: pull_request_target
+permissions:
+  pull-requests: write
+  contents: write
+jobs:
+  call-workflow-passing-data:
+    uses: grafana/transmog/.github/workflows/dependabot-automerge.yml@master
+    with:
+      packages-minor-autoupdate: '["github.com/felixge/httpsnoop","github.com/go-graphite/go-whisper","github.com/go-kit/log","github.com/gogo/protobuf","github.com/golang/protobuf","github.com/golang/snappy","github.com/gorilla/mux","github.com/grafana/dskit","github.com/grafana/metrictank","github.com/grafana/mimir","github.com/kisielk/whisper-go","github.com/mwitkow/go-conntrack","github.com/oklog/run","github.com/oklog/ulid","github.com/opentracing-contrib/go-stdlib","github.com/opentracing/opentracing-go","github.com/pkg/errors","github.com/prometheus/client_golang","github.com/prometheus/common","github.com/serialx/hashring","github.com/stretchr/testify","github.com/uber/jaeger-client-go","github.com/uber/jaeger-lib","github.com/weaveworks/common","golang.org/x/net","google.golang.org/grpc"]'
+    secrets: inherit

Makefile

@@ -1,4 +1,4 @@
-.PHONY: help
+.PHONY: help packages-minor-autoupdate
 
 help:
 	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'
@@ -17,3 +17,13 @@ coverage-show-func: ## Display coverage output
 
 protobuf: ## Runs protoc command to generate pb files
 	bash ./scripts/genprotobuf.sh
+
+packages-minor-autoupdate:
+	go mod edit -json \
+		| jq ".Require \
+			| map(select(.Indirect | not).Path) \
+			| map(select( \
+				. != \"github.com/bradfitz/gomemcache\" \
+				and . != \"github.com/prometheus/prometheus\" \
+			))" \
+		| tr -d '\n' | tr -d '  '