Fix bare month normalization in arxiv_to_publications_correct.py

[Copilot]

PRs #1098/#1099 fixed issue_to_bibtex.py (bibbot) for bare/unquoted month values from DOI BibTeX (e.g. month = june,), but arxiv_to_publications_correct.py (arxivbot) was never patched. Issue #1105 hit the identical failure: two entries silently dropped with error processing BibTeX from DOI: 'june'.

bibtexparser treats unquoted bare words as string references, throwing UndefinedString: 'june' when no such string is defined.

Changes

• bin/arxiv_to_publications_correct.py: Added normalize_month_fields() (identical to the function introduced in Harden DOI BibTeX month normalization in bibbot ingestion #1099) and call it on the raw BibTeX string immediately before bibtexparser.loads(bib), covering both month = june, and month = 'june, variants.

bib = "{".join([bType] + [','.join([id]+rest2)] + rest1[1:])
bib = normalize_month_fields(bib)   # <-- new
bib_db = bibtexparser.loads(bib)