Fix RangeSet::filter() used by Redundant multipath scheduler

[iyangsj]

• Update unit test for RangeSet:filter
• Update test scripts for multipath

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 95.13%. Comparing base (662f3ca) to head (6b75e54).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #253 +/- ## =========================================== - Coverage 95.15% 95.13% -0.02% =========================================== Files 49 49 Lines 33181 33219 +38 =========================================== + Hits 31573 31603 +30 - Misses 1608 1616 +8 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.