Remove SharedFxLookup tests

[elinor-fung]

These were a roundabout/confusing way of testing that we roll forward patch/minor for framework resolution by default and how we resolve dependencies based on assembly version when the dependency is included in multiple frameworks. We have existing tests that are clearer and lighter weight that do this.

Deleted:

• Multiple_SharedFxLookup_NetCoreApp_MinorRollForward_Wins_Over_UberFx
  • two frameworks (uber, netcoreapp), rolls forward on minor version to use netcoreapp, netcoreapp has a higher assembly version, validates that assembly from netcoreapp is used
• Multiple_SharedFxLookup_Uber_Wins_Over_NetCoreApp_On_PatchRollForward
  • two frameworks (uber, netcoreapp), rolls forward on patch version to use netcoreapp, uber has a higher assembly version, validates that assembly from uber is used

These are covered by AppPerAssemblyVersionResolutionMultipleFrameworks and RollForwardMultipleFrameworks.

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[ghost]

Tagging subscribers to this area: @vitek-karas, @agocke, @VSadov
See info in area-owners.md if you want to be subscribed.

Issue Details

---

These were a roundabout/confusing way of testing that we roll forward patch/minor for framework resolution by default and how we resolve dependencies based on assembly version when the dependency is included in multiple frameworks. We have existing tests that are clearer and lighter weight that do this.

Deleted:

• Multiple_SharedFxLookup_NetCoreApp_MinorRollForward_Wins_Over_UberFx
  • two frameworks (uber, netcoreapp), rolls forward on minor version to use netcoreapp, netcoreapp has a higher assembly version, validates that assembly from netcoreapp is used
• Multiple_SharedFxLookup_Uber_Wins_Over_NetCoreApp_On_PatchRollForward
  • two frameworks (uber, netcoreapp), rolls forward on patch version to use netcoreapp, uber has a higher assembly version, validates that assembly from uber is used

These are covered by AppPerAssemblyVersionResolutionMultipleFrameworks and RollForwardMultipleFrameworks.

Author:	elinor-fung
Assignees:	elinor-fung
Labels:	area-Host
Milestone:	-