publish container-structure-test 1.21.1 (#6070)

diff --git a/modules/container_structure_test/1.21.1/MODULE.bazel b/modules/container_structure_test/1.21.1/MODULE.bazel
new file mode 100644
index 0000000..a8199b4
--- /dev/null
+++ b/modules/container_structure_test/1.21.1/MODULE.bazel
@@ -0,0 +1,30 @@
+"Bazel module definition, see https://bazel.build/external/overview#bzlmod"
+module(
+    name = "container_structure_test",
+    compatibility_level = 1,
+    # Replaced dynamically when published
+    version = "1.21.1",
+)
+
+# To run jq
+bazel_dep(name = "aspect_bazel_lib", version = "1.28.0")
+bazel_dep(name = "bazel_skylib", version = "1.6.1")
+bazel_dep(name = "platforms", version = "0.0.9")
+
+ext = use_extension("//:repositories.bzl", "extension")
+use_repo(
+    ext,
+    "structure_test_toolchains",
+    # For testing only
+    "structure_test_st_darwin_amd64",
+    "structure_test_st_darwin_arm64",
+    "structure_test_st_linux_arm64",
+    "structure_test_st_linux_s390x",
+    "structure_test_st_linux_amd64",
+    "structure_test_st_windows_amd64",
+)
+
+register_toolchains("@structure_test_toolchains//:all")
+
+# 0.5.4 is the first version with bzlmod support
+bazel_dep(name = "stardoc", version = "0.5.4", repo_name = "io_bazel_stardoc", dev_dependency = True)
diff --git a/modules/container_structure_test/1.21.1/patches/module_dot_bazel.patch b/modules/container_structure_test/1.21.1/patches/module_dot_bazel.patch
new file mode 100644
index 0000000..0bbb92f
--- /dev/null
+++ b/modules/container_structure_test/1.21.1/patches/module_dot_bazel.patch
@@ -0,0 +1,13 @@
+Index: MODULE.bazel
+===================================================================
+--- MODULE.bazel
++++ MODULE.bazel
+@@ -3,7 +3,7 @@ module(
+     name = "container_structure_test",
+     compatibility_level = 1,
+     # Replaced dynamically when published
+-    version = "0.0.0",
++    version = "1.21.1",
+ )
+ 
+ # To run jq
diff --git a/modules/container_structure_test/1.21.1/presubmit.yml b/modules/container_structure_test/1.21.1/presubmit.yml
new file mode 100644
index 0000000..ee5a576
--- /dev/null
+++ b/modules/container_structure_test/1.21.1/presubmit.yml
@@ -0,0 +1,12 @@
+bcr_test_module:
+  module_path: "bazel/test"
+  matrix:
+    platform: ["debian10", "macos", "ubuntu2004", "windows"]
+    bazel: ["7.x"]
+  tasks:
+    run_tests:
+      name: "Run test module"
+      platform: ${{ platform }}
+      bazel: ${{ bazel }}
+      test_targets:
+        - "//..."
diff --git a/modules/container_structure_test/1.21.1/source.json b/modules/container_structure_test/1.21.1/source.json
new file mode 100644
index 0000000..c53bd31
--- /dev/null
+++ b/modules/container_structure_test/1.21.1/source.json
@@ -0,0 +1,9 @@
+{
+    "url": "https://github.com/GoogleContainerTools/container-structure-test/archive/refs/tags/v1.21.1.tar.gz",
+    "integrity": "sha256-4pB1iF2sZK6I70TW03tvj34c9qpsspj2Qc6W/CeScLw=",
+    "strip_prefix": "container-structure-test-1.21.1",
+    "patch_strip": 0,
+    "patches": {
+        "module_dot_bazel.patch": "sha256-yPhxPTjR4L2uCcNGLM+meosOWzYAlQSm4X+gBaFbAV0="
+    }
+}
diff --git a/modules/container_structure_test/metadata.json b/modules/container_structure_test/metadata.json
index 69dc6cf..383d291 100644
--- a/modules/container_structure_test/metadata.json
+++ b/modules/container_structure_test/metadata.json
@@ -21,7 +21,8 @@
         "1.15.0",
         "1.16.0",
         "1.19.1",
-        "1.20.0"
+        "1.20.0",
+        "1.21.1"
     ],
     "yanked_versions": {}
 }