SPMI: Fix accumulation of repro files (#91194)

The existing logic to create repro .mc files would ask superpmi to place
them into a temporary directory, then copy the .mc files to the final
directory. However, when multiple .mch files are being replayed, this
means that we continuously accumulate more and more .mc files into the
temporary directory which are then copied to the final directory for
each .mch file being replayed.

Switch shutil.copy2 to shutil.move to empty the directory between each
replay.

src/coreclr/scripts/superpmi.py

@@ -1310,8 +1310,8 @@ def save_repro_mc_files(temp_location, coreclr_args, artifacts_base_name, repro_
         repro_files = []
         for item in mc_files:
             repro_files.append(os.path.join(repro_location, os.path.basename(item)))
-            logging.debug("Copying %s -> %s", item, repro_location)
-            shutil.copy2(item, repro_location)
+            logging.debug("Moving %s -> %s", item, repro_location)
+            shutil.move(item, repro_location)
 
         logging.info("")
         logging.info("Repro {} .mc file(s) created for failures:".format(len(repro_files)))
@@ -1376,7 +1376,7 @@ def replay(self):
 
             common_flags = [
                 "-v", "ewi",  # display errors, warnings, missing, jit info
-                "-r", os.path.join(temp_location, "repro")  # Repro name, create .mc repro files
+                "-r", os.path.join(temp_location, "repro") # Repro name prefix, create .mc repro files
             ]
 
             if self.coreclr_args.altjit:
@@ -1724,7 +1724,7 @@ def replay_with_asm_diffs(self):
                     "-v", "ewi",  # display errors, warnings, missing, jit info
                     "-f", fail_mcl_file,  # Failing mc List
                     "-diffsInfo", diffs_info,  # Information about diffs
-                    "-r", os.path.join(temp_location, "repro"),  # Repro name, create .mc repro files
+                    "-r", os.path.join(temp_location, "repro"),  # Repro name prefix, create .mc repro files
                     "-baseMetricsSummary", base_metrics_summary_file, # Create summary of metrics we can use to get total code size impact
                     "-diffMetricsSummary", diff_metrics_summary_file,
                 ]