Fix regression: time stamp test suite failures

src/ocrmypdf/pdfa.py

@@ -143,6 +143,7 @@ def decode_pdf_date(s: str) -> datetime:
 
     if s.startswith('D:'):
         s = s[2:]
+    s = s.replace("'", "")  # Remove apos from PDF time strings
     for fmt in pdfmark_date_fmts:
         try:
             return datetime.strptime(s, fmt)

tests/test_metadata.py

@@ -19,6 +19,7 @@
 import pytest
 import PyPDF2 as pypdf
 import datetime
+from datetime import timezone
 
 from ocrmypdf.pdfa import file_claims_pdfa, encode_pdf_date, decode_pdf_date
 from ocrmypdf.exceptions import ExitCode
@@ -150,6 +151,6 @@ def test_creation_date_preserved(spoof_tesseract_noop, output_type, resources,
     # We expect that the modified date is quite recent
     date_after = decode_pdf_date(after['/ModDate'])
     assert seconds_between_dates(
-        date_after, datetime.datetime.utcnow()) < 1000
+        date_after, datetime.datetime.now(timezone.utc)) < 1000