LogQL: Add unwrap bytes() conversion function

[jkellerer]

What this PR does / why we need it:

This PR adds the bytes() conversion function to unwrap. While LogQL allows parsing bytes and duration values, the unwrap conversion provides only a method to handle duration, however many log files contain human readable byte values which should be convertible to raw bytes.

With this PR queries like the following are supported:

sum_over_time(
    {app="restic"}
        |~ `Added to the repo:.+`
        | regexp `.+repo: (?P<size>[\d\.]+ \w+)`
        | unwrap bytes(size)[10m]
)

For a log line like this:

Added to the repo: 8.369 MiB

Which issue(s) this PR fixes:
None

Special notes for your reviewer:
Parser was modified (including generated code).

Checklist

• Documentation added
• Tests updated

[CLAassistant]

All committers have signed the CLA.

[cyriltovena]

LGTM

Really big thanks for this, we were supposed to add it soon, but guess you beat us at it.

[jkellerer]

Thanks a lot for the fast response!
Appreciate that it was added as my workaround is not pretty...