refactor: remove simapp references from x/bank and x/slashing tests (#12897)

## Description

There are still some references to simapp in `x/bank` and `x/slashing`.  This patch removes them.  Somewhat related to forming tests also:

- Flags `LegacySubspace exported.Subspace` as ``optional:"true"`` since x/params is moving to deprecation 



---

### Author Checklist

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please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/main/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

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your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

x/capability/capability_test.go

@@ -33,10 +33,13 @@ type CapabilityTestSuite struct {
 func (suite *CapabilityTestSuite) SetupTest() {
 	suite.memKey = storetypes.NewMemoryStoreKey("testingkey")
 
-	app, err := simtestutil.SetupWithBaseAppOption(testutil.AppConfig,
-		func(ba *baseapp.BaseApp) {
-			ba.MountStores(suite.memKey)
-		},
+	startupCfg := simtestutil.DefaultStartUpConfig()
+	startupCfg.BaseAppOption = func(ba *baseapp.BaseApp) {
+		ba.MountStores(suite.memKey)
+	}
+
+	app, err := simtestutil.SetupWithConfiguration(testutil.AppConfig,
+		startupCfg,
 		&suite.cdc,
 		&suite.keeper,
 	)