BUG: Fix precise_xstrtod segfault on long exponent
- [x] closes #38753
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

@snowman2 can you check if this branch returns behavior to what you had before 1.2?