Actions `cluster:admin/repository/analyze/blob` and `cluster:admin/repository/analyze/register` and so on are only invoked via the transport service, they do not need to register as client actions so we can drop the `ActionType` instance. Instead the root `RepositoryAnalyzeAction` should create and register all these transport actions itself. But even the root `RepositoryAnalyzeAction` should not be an `ActionType` derivative, we should just declare an `ActionType` instance directly. Moreover we can use `ActionType#localOnly` since the client action does not run on remote clusters.
x-pack/plugin/snapshot-repo-test-kit/src/main/java/org/elasticsearch/repositories/blobstore/testkit/BlobAnalyzeAction.java
super.writeTo(out);
            out.writeString(repositoryName);
            out.writeString(blobPath);
            out.writeString(blobName);
            out.writeVLong(targetLength);
            out.writeLong(seed);
            out.writeCollection(nodes);
            out.writeVInt(readNodeCount);
            out.writeVInt(earlyReadNodeCount);
            out.writeBoolean(readEarly);
            out.writeBoolean(writeAndOverwrite);
            if (out.getTransportVersion().onOrAfter(TransportVersions.V_7_14_0)) {
                out.writeBoolean(abortWrite);
            e if (abortWrite) {
                throw new IllegalStateException("cannot send abortWrite request on transport version [" + out.getTransportVersion() + "]");
            }
        }
        @Override
        public ActionRequestValidationException validate() {
            return null;
        }
        @Override
        public String getDescription() {
            return "blob analysis ["
                + repositoryName
                + ":"
                + blobPath
                + "/"
                + blobName
                + ", length="