[PSRule] Discuss PSRule validation results and update modules/module tests accordingly

[eriqua]

Analyze the output of PSRule validation. List all modules to be updated and open separated issues for each.

For each failed rule we should:

• either fix the module/module test to have it compliant
• or suppress the rule if not making sense in our scenario,documenting the reason

Example

List of failed rules after running PSRule validation on RG, KV and VNET modules:

• Tags should be added to common tests, the ones aiming to validate all possible parameters for a module
• Purge keyvault should be suppressed. It doesn't make sense for our testing scenario because we want to clean up the environment after each test

Following the list of rules to be fixed:

### Tasks
- [ ] Azure/ResourceModules#2666
- [ ] Azure/ResourceModules#2667
- [ ] Azure/ResourceModules#2668
- [ ] https://github.com/Azure/ResourceModules/issues/3894
- [ ] https://github.com/Azure/ResourceModules/issues/3896
- [x] https://github.com/Azure/ResourceModules/issues/3418
- [ ] https://github.com/Azure/ResourceModules/issues/3917
- [ ] https://github.com/Azure/bicep-registry-modules/issues/2377
- [x] https://github.com/Azure/bicep-registry-modules/issues/2399
- [ ] [PSRule] Fix Rule Azure.VM.DiskSizeAlignment
- [ ] [PSRule] Fix Rule Azure.VM.Standalone
- [ ] [PSRule] Fix Rule Azure.VM.UseHybridUseBenefit
- [ ] [PSRule] Fix Rule Azure.VNET.UseNSGs
- [ ] [PSRule] Fix Rule Azure.WebPubSub.ManagedIdentity
- [ ] [PSRule] Fix Rule Azure.AppService.PlanInstanceCount
- [ ] [PSRule] Fix Rule Azure.Defender.AppServices
- [ ] [PSRule] Fix Rule Azure.Defender.Containers
- [ ] [PSRule] Fix Rule Azure.Defender.Servers
- [ ] [PSRule] Fix Rule Azure.Defender.SQL
- [ ] [PSRule] Fix Rule Azure.Defender.SQLOnVM
- [ ] [PSRule] Fix Rule Azure.Defender.Storage
- [ ] [PSRule] Fix Rule Azure.LB.Probe
- [ ] [PSRule] Fix Rule Azure.ServiceFabric.AAD
- [ ] [PSRule] Fix Rule Azure.SignalR.ManagedIdentity
- [ ] [PSRule] Fix Rule Azure.SQL.AAD
- [ ] [PSRule] Fix Rule Azure.SQL.Auditing
- [ ] [PSRule] Fix Rule Azure.SQL.DefenderCloud
- [ ] [PSRule] Fix Rule Azure.Storage.ContainerSoftDelete
- [ ] [PSRule] Fix Rule Azure.Storage.Firewall
- [ ] [PSRule] Fix Rule Azure.Storage.SoftDelete
- [ ] [PSRule] Fix Rule Azure.Deployment.AdminUsername
- [ ] https://github.com/Azure/ResourceModules/issues/3987
- [ ] https://github.com/Azure/ResourceModules/issues/3997

[eriqua]

Suggestion: keep in triage with the needsfurtherdiscussion label until refinement completion. This will include the list of modules to be fixed based on the outcome of issue #2425