Add comments to avoid blocking in sequence and resolve stages

src/commit_pipeline.cpp

@@ -79,6 +79,7 @@ void CommitPipeline::submit_batch(std::span<PipelineEntry> entries) {
   // Guard destructor publishes batch to stage 0
 }
 
+// AVOID BLOCKING IN THIS STAGE!
 void CommitPipeline::run_sequence_stage() {
 
   int64_t next_version = 1;
@@ -157,6 +158,7 @@ void CommitPipeline::run_sequence_stage() {
   }
 }
 
+// AVOID BLOCKING IN THIS STAGE!
 void CommitPipeline::run_resolve_stage() {
   for (int shutdowns_received = 0; shutdowns_received < 2;) {
     auto guard = pipeline_.acquire<1, 0>(/*maxBatch*/ 1);