repl: no RegExp side effects for static properties

Preserve all RegExp static properties

• RegExp.$1 to RegExp.9
• input, lastMatch, lastParen
• leftContext and rightContext

Fixes: https://github.com/nodejs/node/issues/18931

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

Affected core subsystem(s)

repl

cc: @bnoordhuis