scripted-diff: rename versionbitscache

Summary:

-BEGIN VERIFY SCRIPT-
sed -i -e 's/versionbitscache/g_versionbitscache/g' $(git grep -l versionbitscache)
-END VERIFY SCRIPT-

This is a partial backport of core#19438
https://github.com/bitcoin/bitcoin/pull/19438/commits/c64b2c6a0f79369624ae96b2e3d579d50aae4de6

Depends on D12223

Test Plan: ninja all check-all

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D12221