android: bump versionCode on tag to trigger fdroid builds

Previously, versionCode was only set by the Play Store builder and never committed back to the repo, so fdroid wouldn't detect updates. This bumps versionCode at tag time for fdroid. The builder still overrides it with the Play Store value

Updates tailscale/tailscale#18969

Signed-off-by: kari-ts <kari@tailscale.com>

Author: kari-ts

Makefile

@@ -270,13 +270,16 @@ androidpath:
 	@echo "export ANDROID_SDK_ROOT=$(ANDROID_SDK_ROOT)"
 	@echo 'export PATH=$(ANDROID_HOME)/cmdline-tools/latest/bin:$(ANDROID_HOME)/platform-tools:$$PATH'
 
-.PHONY: tag_release
-tag_release: debug-symbols tailscale.version ## Tag the current commit with the current version
-	source tailscale.version && git tag -a "$${VERSION_LONG}" -m "OSS and Version updated to $${VERSION_LONG}"
-
-.PHONY: bumposs ## Bump to the latest oss and update the versions.
-bumposs: update-oss tailscale.version
-	source tailscale.version && git commit -sm "android: bump OSS" -m "OSS and Version updated to $${VERSION_LONG}" go.toolchain.rev android/build.gradle go.mod go.sum
+## Bump versionCode, amend the current commit, and tag it
+tag_release: debug-symbols tailscale.version bump_version_code 
+	git add android/build.gradle                                                                                                                                             
+	git commit --amend --no-edit
+	source tailscale.version && git tag -a "$${VERSION_LONG}" -m "OSS and Version updated to $${VERSION_LONG}"      
+
+## Bump to the latest oss, increment versionCode, and tag. 
+.PHONY: bumposs                                                                                                            
+  bumposs: update-oss tailscale.version bump_version_code
+	source tailscale.version && git commit -sm "android: bump OSS" -m "OSS and Version updated to $${VERSION_LONG}" go.toolchain.rev android/build.gradle go.mod go.sum      
 	source tailscale.version && git tag -a "$${VERSION_LONG}" -m "OSS and Version updated to $${VERSION_LONG}"
 
 .PHONY: bump_version_code ## Bump the version code in build.gradle