Handle pre-releases in release-notes make target

Author: Cecile Robert-Michon

Makefile

@@ -419,6 +419,10 @@ set-manifest-pull-policy:
 ## --------------------------------------
 
 RELEASE_TAG ?= $(shell git describe --abbrev=0 2>/dev/null)
+# if the release tag contains a hyphen, treat it as a pre-release
+ifneq (,$(findstring -,$(RELEASE_TAG)))
+    PRE_RELEASE=true
+endif
 # the previous release tag, e.g., v0.3.9, excluding pre-release tags
 PREVIOUS_TAG ?= $(shell git tag -l | grep -E "^v[0-9]+\.[0-9]+\.[0-9]+$$" | sort -V | grep -B1 $(RELEASE_TAG) | head -n 1 2>/dev/null)
 RELEASE_DIR ?= out
@@ -484,9 +488,11 @@ release-alias-tag: # Adds the tag to the last build tag.
 
 .PHONY: release-notes
 release-notes: $(RELEASE_NOTES) $(RELEASE_NOTES_DIR)
-	$(RELEASE_NOTES) --org $(GIT_ORG_NAME) --repo $(GIT_REPO_NAME) --branch $(RELEASE_BRANCH)  --start-rev $(PREVIOUS_TAG) --end-rev $(RELEASE_TAG) --output $(RELEASE_NOTES_DIR)/tmp-release-notes.md
-	sed 's/\[SIG Cluster Lifecycle\]//g' $(RELEASE_NOTES_DIR)/tmp-release-notes.md > $(RELEASE_NOTES_DIR)/release-notes-$(RELEASE_TAG).md
-	rm -f $(RELEASE_NOTES_DIR)/tmp-release-notes.md
+	@if [ -n "${PRE_RELEASE}" ]; then echo ":rotating_light: This is a RELEASE CANDIDATE. Use it only for testing purposes. If you find any bugs, file an [issue](https://github.com/kubernetes-sigs/cluster-api-provider-azure/issues/new)." > $(RELEASE_NOTES_DIR)/release-notes-$(RELEASE_TAG).md; \
+	else $(RELEASE_NOTES) --org $(GIT_ORG_NAME) --repo $(GIT_REPO_NAME) --branch $(RELEASE_BRANCH)  --start-rev $(PREVIOUS_TAG) --end-rev $(RELEASE_TAG) --output $(RELEASE_NOTES_DIR)/tmp-release-notes.md; \
+	sed 's/\[SIG Cluster Lifecycle\]//g' $(RELEASE_NOTES_DIR)/tmp-release-notes.md > $(RELEASE_NOTES_DIR)/release-notes-$(RELEASE_TAG).md; \
+	rm -f $(RELEASE_NOTES_DIR)/tmp-release-notes.md; \
+	fi
 
 ## --------------------------------------
 ## Development