fix: remove dependency on tendermint internal library (#12368)

## Description

This is an oft added function for many projects that's probably more clear to implement as needed, but is probably mostly just a gap in the standard library. 

This function is removed in more recent versions of tendermint (as tendermint no longer uses it.) 

---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
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

*All items are required. Please add a note if the item is not applicable and please add
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)

store/types/store.go

@@ -5,7 +5,6 @@ import (
 	"io"
 
 	abci "github.com/tendermint/tendermint/abci/types"
-	tmstrings "github.com/tendermint/tendermint/libs/strings"
 	dbm "github.com/tendermint/tm-db"
 
 	pruningtypes "github.com/cosmos/cosmos-sdk/pruning/types"
@@ -64,7 +63,12 @@ func (s *StoreUpgrades) IsAdded(key string) bool {
 	if s == nil {
 		return false
 	}
-	return tmstrings.StringInSlice(key, s.Added)
+	for _, added := range s.Added {
+		if key == added {
+			return true
+		}
+	}
+	return false
 }
 
 // IsDeleted returns true if the given key should be deleted

x/staking/keeper/msg_server.go

@@ -9,7 +9,6 @@ import (
 	"google.golang.org/grpc/status"
 
 	"github.com/armon/go-metrics"
-	tmstrings "github.com/tendermint/tendermint/libs/strings"
 
 	cryptotypes "github.com/cosmos/cosmos-sdk/crypto/types"
 	"github.com/cosmos/cosmos-sdk/telemetry"
@@ -70,7 +69,15 @@ func (k msgServer) CreateValidator(goCtx context.Context, msg *types.MsgCreateVa
 
 	cp := ctx.ConsensusParams()
 	if cp != nil && cp.Validator != nil {
-		if !tmstrings.StringInSlice(pk.Type(), cp.Validator.PubKeyTypes) {
+		pkType := pk.Type()
+		hasKeyType := false
+		for _, keyType := range cp.Validator.PubKeyTypes {
+			if pkType == keyType {
+				hasKeyType = true
+				break
+			}
+		}
+		if !hasKeyType {
 			return nil, sdkerrors.Wrapf(
 				types.ErrValidatorPubKeyTypeNotSupported,
 				"got: %s, expected: %s", pk.Type(), cp.Validator.PubKeyTypes,