Add additional make targets to run all golden tests

.sync.yml

@@ -17,3 +17,7 @@ docs/antora.yml:
       - custom-route-legacy
       - custom-route-legacy-4.7
       - custom-route-managed-tls
+
+Makefile:
+  includes:
+    - Makefile.additional.mk

Makefile

@@ -12,6 +12,7 @@ SHELL := bash
 .SUFFIXES:
 
 include Makefile.vars.mk
+include Makefile.additional.mk
 
 .PHONY: help
 help: ## Show this help

Makefile.additional.mk

@@ -0,0 +1,13 @@
+instances=$(shell find ./tests -maxdepth 1 -type f -name '*.yml')
+
+.PHONY: all-golden-diff
+golden-diff-all: recursive_target=golden-diff
+golden-diff-all: $(instances) ## Run golden-diff for all instances. Note: this doesn't work when running make with multiple parallel job (-j != 1).
+
+.PHONY: all-golden-diff
+gen-golden-all: recursive_target=gen-golden
+gen-golden-all: $(instances) ## Run gen-golden for all instances. Note: this doesn't work when running make with multiple parallel job (-j != 1).
+
+.PHONY: $(instances)
+$(instances):
+	$(MAKE) $(recursive_target) -e instance=$(basename $(@F))