Conditions can refer to the groups array that is a list of the preceding groups.
This commit adds support to the verification for those conditions.
This commit also adds some tests to the parsing and condition matching
to ensure everything works as expected.
PR Close#38164
Currently, when verifying our pullapprove configuration, we don't
respect modifications to the set of files in a condition.
e.g. It's not possible to do the following:
```
contains_any_globs(files.exclude(...), [
```
This prevents us from having codeowner groups which match a directory,
but want to filter out specific sub directories. For example, `fw-core`
matches all files in the core package. We want to exclude the schematics
from that glob. Usually we do this by another exclude condition.
This has a *significant* downside though. It means that fw-core will not
be requested if a PR changes schematic code, _and_ actual fw-core code.
To support these conditions, the pullapprove verification tool is
refactored, so that it no longer uses Regular expressions for parsing,
but rather evaluates the code through a dynamic function. This is
possible since the conditions are written in simple Python that can
be run in NodeJS too (with small modifications/transformations).
PR Close#36661
Andrew Scott
Joey Perrott
Paul Gschwendtner