Adjust Docker build defaults

Makefile

@@ -1,8 +1,13 @@
 # Multi-platform Docker build and publish for CyberChef
 
-IMAGE_NAME ?= ghcr.io/gchq/cyberchef
+IMAGE_NAME ?= ghcr.io/mkilijanek/cyberchef
 PLATFORMS ?= linux/amd64,linux/arm64
 MONTHLY_TAG ?= $(shell date +%Y-%m)
+SBOM ?= false
+PROVENANCE ?= false
+
+SBOM_FLAG := $(if $(filter true,$(SBOM)),--sbom=true,)
+PROVENANCE_FLAG := $(if $(filter true,$(PROVENANCE)),--provenance=true,)
 
 .PHONY: check-branch build publish scan
 
@@ -19,8 +24,8 @@ build: check-branch
                 --platform $(PLATFORMS) \
                 --tag $(IMAGE_NAME):latest \
                 --tag $(IMAGE_NAME):$(MONTHLY_TAG) \
-		--sbom=true \
-		--provenance=true \
+                $(SBOM_FLAG) \
+                $(PROVENANCE_FLAG) \
                 --output=type=docker \
                 .
 
@@ -30,8 +35,8 @@ publish: check-branch
                 --platform $(PLATFORMS) \
                 --tag $(IMAGE_NAME):latest \
                 --tag $(IMAGE_NAME):$(MONTHLY_TAG) \
-		--sbom=true \
-		--provenance=true \
+                $(SBOM_FLAG) \
+                $(PROVENANCE_FLAG) \
                 --push \
                 .
         $(MAKE) scan