Today if we detect concurrent modification of a snapshot repository then we mark it with `CORRUPTED_REPO_GEN` which blocks further writes to try and prevent additional damage to its contents. You can remove the marker by calling the register-repository API again, but this API will discard no-op re-registrations without taking any action. You can work around this by unregistering the repository first (which may be impossible if it's still in use for searchable snapshots) or by re-registering it with some trivial setting change (which seems hacky).

We should not consider it a no-op re-registration if the repository is currently marked with `CORRUPTED_REPO_GEN`, because doing this re-registration will re-read the repo contents and clear the corruption marker and therefore is not a no-op.
server/src/internalClusterTest/java/org/elasticsearch/snapshots/ConcurrentSnapshotsIT.java
unblockNode(repoName, masterName);
        networkDisruption.stopDisrupting();
        ensureStableCluster(4);
        try {
            deleteAllSnapshotsWithIndex.get();
        } catch (Exception ignored) {
            
            
            
        }
    }
    public void testStatusMultipleSnapshotsMultipleRepos() throws Exception {
        internalCluster().startMasterOnlyNode();
        
        
        final String dataNode = startDataNodeWithLargeSnapshotPool();
        final String blockedRepoName = "test-repo-blocked-1";
        final String otherBlockedRepoName = "test-repo-blocked-2";
        createRepository(blockedRepoName, "mock");
        createRepository(otherBlockedRepoName, "mock");
        createIndexWithContent("test-index");
        final ActionFuture<CreateSnapshotResponse> createSlowFuture1 = startFullSnapshotBlockedOnDataNode(
            "blocked-snapshot",
            blockedRepoName,
            dataNode
        );
        final ActionFuture<CreateSnapshotResponse> createSlowFuture2 = startFullSnapshotBlockedOnDataNode(
            "blocked-snapshot-2",
            blockedRepoName,