[Interop] Rebuild dart image (#36562)

This is the same change as in #36556, but the change was committed without the second commit that existed in the PR (due to a very wide wait-for-CI-before-syncing race).

The sha here is what's currently in testing-images-public. I don't know where it came from but it has the proper update.

Closes #36562

PiperOrigin-RevId: 631871629

tools/bazelify_tests/dockerimage_current_versions.bzl

@@ -72,7 +72,7 @@ DOCKERIMAGE_CURRENT_VERSIONS = {
     "tools/dockerfile/grpc_artifact_python_musllinux_1_1_x86.current_version": "docker://us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_artifact_python_musllinux_1_1_x86@sha256:c288f83435186ee675d004ee52c93195a51201bf2b5fe92581584d977a2499a3",
     "tools/dockerfile/interoptest/grpc_interop_aspnetcore.current_version": "docker://us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_interop_aspnetcore@sha256:8e2e732e78724a8382c340dca72e7653c5f82c251a3110fa2874cc00ba538878",
     "tools/dockerfile/interoptest/grpc_interop_cxx.current_version": "docker://us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_interop_cxx@sha256:e5a474d33773d52ec6a8abbe2d61ee0c2a9c2b5f48793a5ea3b82c4445becf3f",
-    "tools/dockerfile/interoptest/grpc_interop_dart.current_version": "docker://us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_interop_dart@sha256:c44c44706e28c328489ab9cbbf1f2940855c4c341639fbda76b2fc1d561e3383",
+    "tools/dockerfile/interoptest/grpc_interop_dart.current_version": "docker://us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_interop_dart@sha256:4915a280788126dad029858eb384dbbef2dc18cadccb434df6450dfd7a4929f2",
     "tools/dockerfile/interoptest/grpc_interop_go.current_version": "docker://us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_interop_go@sha256:889e7ff34399a5e16af87940d1eaa239e56da307f7faca3f8f1d28379c2e3df3",
     "tools/dockerfile/interoptest/grpc_interop_go1.11.current_version": "docker://us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_interop_go1.11@sha256:f2fe3a0a581c687ee4217bf58fd42b18bb1f63d3d006f1b67379ff553b0e23c6",
     "tools/dockerfile/interoptest/grpc_interop_go1.16.current_version": "docker://us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_interop_go1.16@sha256:3767f47c9d06584c6c07b7ab536e13f3e87550330e6c2652ad288d3a72b0de23",

tools/dockerfile/interoptest/grpc_interop_dart.current_version

@@ -1 +1 @@
-us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_interop_dart:c795310ab447f964b848b656e083196e0ece2dfc@sha256:c44c44706e28c328489ab9cbbf1f2940855c4c341639fbda76b2fc1d561e3383
+us-docker.pkg.dev/grpc-testing/testing-images-public/grpc_interop_dart:c795310ab447f964b848b656e083196e0ece2dfc@sha256:4915a280788126dad029858eb384dbbef2dc18cadccb434df6450dfd7a4929f2