Fix partition setup

[carllin]

Problem

1. Partitions were not being created properly due to misuse of tc on ingress traffic.
2. Improper "default" filter was causing other unintended traffic to be filtered (causing validators within the same partition to be unable to communicate)
3. Cleanup partitions was not being done correctly, off by one error in identifying a validators partitions prevented multiple partitions from being simulated consecutively.

Summary of Changes

1. Set up partitions by redirecting ingress traffic to the egress traffic stream of a virtual interface, ifb0. This allows ingress traffic to then be shaped using stateful qdiscs and filters, allowing for originally intended behavior of dropping incoming packets based on tos field.
2. Setup a proper "catch-all" filter to allow validators on same partition to talk to each other.
3. Simplify cleanup logic

On a 4 node network, 50-50 split, 2-min partition:

Partitions actually seem to be happening in gossip now!

Both validators on the of the the bootstrap leader continue to move during partition (76% of the stake):

Validators on other side get stuck as expected (24% of the stake):

Fixes #

[codecov]

Codecov Report

Merging #9386 into master will decrease coverage by 0.0%.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           master   #9386     +/-   ##
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- Coverage    81.1%   81.1%   -0.1%     
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  Files         276     276             
  Lines       62110   62110             
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- Hits        50429   50427      -2     
- Misses      11681   11683      +2     

Pull request has been modified.