Enable color output in govulncheck (go-gitea#34012)

Make `govulncheck` show color, which by default it doesn't for some
reason.

(cherry picked from commit 2089401)

Author: silverwind

Makefile

@@ -523,7 +523,7 @@ lint-yaml: .venv
 
 .PHONY: security-check
 security-check:
-	go run $(GOVULNCHECK_PACKAGE) ./...
+	go run $(GOVULNCHECK_PACKAGE) -show color ./...
 
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 # Development and testing targets