Strip problematic private escape sequences

[dosisod]

Type of changes

• [x] Bug fix
• [ ] New feature
• [ ] Documentation / docstrings
• [ ] Tests
• [ ] Other

Checklist

• [x] I've run the latest black with default args on new code.
• [x] I've updated CHANGELOG.md and CONTRIBUTORS.md where appropriate.
• [x] I've added tests for new code.
• [x] I accept that @willmcgugan may be pedantic in the code review.

Description

"Private escape sequences" are escape sequences that are reserved for private use, though \x1b7 and \x1b8 are commonly used for storing and restoring the current cursor position. When those escape codes are not stripped the cursor jumps around and causes Rich to write garbage output. An example of a program that uses this cursor store/restore functionality is the APK package manager in Alpine Linux:

https://gitlab.alpinelinux.org/alpine/apk-tools/-/blob/48d91f482eb48a0a107b714ee183bb7e07782e14/src/print.c#L232-240

This commit updates the ANSI parser to ignore the \x1b0-\x1b? escape sequences, thus preventing them from being printed and causing havoc.