ci: install pcre1 dev package for explicit --with-pcre jobs

[Easton97-Jens]

Motivation

• Ensure CI exercises both the default PCRE2 path and the explicit PCRE1 path (--with-pcre) and that the latter has the required development package available.

Description

• Added libpcre3-dev to the Linux dependency installation list in .github/workflows/ci_new.yml so --with-pcre matrix jobs have PCRE1 headers/libs.
• Kept the CI configure matrix that includes both with pcre2 (default) and with pcre entries so both regex engine code paths are tested.

Testing

• Searched the workflow for relevant dependency and matrix entries with rg to locate insertion points and confirm affected blocks.
• Applied an automated Python edit to insert libpcre3-dev into .github/workflows/ci_new.yml and verified the replacement completed successfully.
• Verified counts and presence of libpcre3-dev, label: "with pcre", and with pcre2 (default) in the workflow via a small Python sanity-check script (all checks succeeded).

---

Codex Task