Expand run folder to 4 digits in report backfill script

webservice/add_reports.py

 """Backfill reports to myMdC from job databases before we started injecting them"""
 import argparse
 import os.path
+import re
 import shlex
 import sys
 import sqlite3
@@ -36,6 +37,11 @@ for i, r in enumerate(rows):
         print("Couldn't find report path in %r", cmd_args)
         continue
 
+    # Workaround: we retrospectively renamed folders like 'r67' to 'r0067'.
+    def runnr_sub(m: re.Match):
+        return f'/r{m[1].zfill(4)}/'
+    report_path = re.sub(r'/r(\d{1,3})/', runnr_sub, report_path, count=1)
+
     if not os.path.isfile(report_path):
         print(f"Report file {report_path} missing (p{r['proposal']}, r{r['run']})")
         continue