matrix subaction

Signed-off-by: CrazyMax <1951866+crazy-max@users.noreply.github.com>

test/group-with-platform/docker-bake.hcl

@@ -0,0 +1,36 @@
+group "validate" {
+  targets = ["lint", "lint-gopls", "validate-vendor", "validate-docs"]
+}
+
+target "lint" {
+  dockerfile = "./hack/dockerfiles/lint.Dockerfile"
+  output = ["type=cacheonly"]
+  platforms = [
+    "darwin/amd64",
+    "darwin/arm64",
+    "linux/amd64",
+    "linux/arm64",
+    "linux/s390x",
+    "linux/ppc64le",
+    "linux/riscv64",
+    "windows/amd64",
+    "windows/arm64"
+  ]
+}
+
+target "lint-gopls" {
+  inherits = ["lint"]
+  target = "gopls-analyze"
+}
+
+target "validate-vendor" {
+  dockerfile = "./hack/dockerfiles/vendor.Dockerfile"
+  target = "validate"
+  output = ["type=cacheonly"]
+}
+
+target "validate-docs" {
+  dockerfile = "./hack/dockerfiles/docs.Dockerfile"
+  target = "validate"
+  output = ["type=cacheonly"]
+}