feat: upgrading alpine and kustomize to align with latest flux release

Signed-off-by: Steven Wade <steven@stevenwade.co.uk>

Author: swade1987

Diff for: Dockerfile

@@ -1,10 +1,10 @@
-FROM alpine:3.21.2
+FROM alpine:3.21.3
 
 RUN apk update && apk --no-cache add bash curl git
 
 SHELL ["/bin/bash", "-o", "pipefail", "-c"]
 
-ARG KUSTOMIZE=5.4.3
+ARG KUSTOMIZE=5.6.0
 RUN curl -sL https://github.com/kubernetes-sigs/kustomize/releases/download/kustomize%2Fv${KUSTOMIZE}/kustomize_v${KUSTOMIZE}_linux_amd64.tar.gz | \
 tar xz && mv kustomize /usr/local/bin/kustomize
 

Diff for: Makefile

@@ -16,4 +16,4 @@ build:
 	docker buildx build --build-arg BUILDPLATFORM=$(BUILDPLATFORM) --build-arg TARGETARCH=$(GOARCH) -t local/$(PROJNAME) .
 
 scan: build
-	trivy --light -s "UNKNOWN,MEDIUM,HIGH,CRITICAL" --exit-code 1 local/$(PROJNAME)
+	trivy image -s "UNKNOWN,MEDIUM,HIGH,CRITICAL" --exit-code 1 local/$(PROJNAME)