Add next hop interface in route row attribute

[haverma]

• this will avoid collapsing attribute changes when the only change is for next hop interface

[batfish-bot]

This change is 

[progwriter]

Reviewed 3 of 3 files at r1.
Reviewable status: complete! all files reviewed, all discussions resolved

[codecov]

Codecov Report

Merging #4802 into master will decrease coverage by 0.02%.
The diff coverage is 85.71%.

@@             Coverage Diff              @@
##             master    #4802      +/-   ##
============================================
- Coverage     75.43%   75.41%   -0.03%     
+ Complexity    28544    28530      -14     
============================================
  Files          2281     2281              
  Lines        112112   112119       +7     
  Branches      13482    13483       +1     
============================================
- Hits          84572    84552      -20     
- Misses        21072    21086      +14     
- Partials       6468     6481      +13

Impacted Files	Coverage Δ	Complexity Δ
...rg/batfish/question/routes/RoutesAnswererUtil.java	92.12% <100%> (+0.02%)	107 <0> (ø)	⬇️
...org/batfish/question/routes/RouteRowAttribute.java	83.09% <83.33%> (+0.02%)	17 <1> (+1)	⬆️
...org/batfish/datamodel/flow/BidirectionalTrace.java	79.54% <0%> (-4.55%)	13% <0%> (-1%)
...src/main/java/org/batfish/coordinator/PoolMgr.java	60.67% <0%> (-4.5%)	14% <0%> (-2%)
...java/org/batfish/symbolic/state/EdgeStateExpr.java	73.91% <0%> (-4.35%)	10% <0%> (-1%)
...c/main/java/org/batfish/dataplane/rib/RibTree.java	89.58% <0%> (-4.17%)	27% <0%> (-1%)
...ain/java/org/batfish/symbolic/IngressLocation.java	65.78% <0%> (-2.64%)	15% <0%> (-1%)
...col/src/main/java/org/batfish/role/InferRoles.java	90.9% <0%> (-1.52%)	65% <0%> (-2%)
...ain/java/org/batfish/coordinator/WorkQueueMgr.java	70.84% <0%> (-0.59%)	90% <0%> (-1%)
...java/org/batfish/dataplane/ibdp/VirtualRouter.java	87.63% <0%> (-0.34%)	252% <0%> (-2%)
... and 2 more