Bump github.com/cosmos/iavl from 0.15.0-rc1 to 0.15.0-rc2 (#7064)

* Bump github.com/cosmos/iavl from 0.15.0-rc1 to 0.15.0-rc2

Bumps [github.com/cosmos/iavl](https://github.com/cosmos/iavl) from 0.15.0-rc1 to 0.15.0-rc2.
- [Release notes](https://github.com/cosmos/iavl/releases)
- [Changelog](https://github.com/cosmos/iavl/blob/master/CHANGELOG.md)
- [Commits](https://github.com/cosmos/iavl/compare/v0.15.0-rc1...v0.15.0-rc2)

Signed-off-by: dependabot[bot] <support@github.com>

* fix test

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Marko <marbar3778@yahoo.com>
Co-authored-by: Alexander Bezobchuk <alexanderbez@users.noreply.github.com>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>
Co-authored-by: Aleksandr Bezobchuk <aleks.bezobchuk@gmail.com>

store/rootmulti/store_test.go

@@ -159,19 +159,6 @@ func TestMultistoreCommitLoad(t *testing.T) {
 	require.Nil(t, err)
 	commitID = getExpectedCommitID(store, ver)
 	checkStore(t, store, commitID, commitID)
-
-	// XXX: commit this older version
-	commitID = store.Commit()
-	expectedCommitID = getExpectedCommitID(store, ver+1)
-	checkStore(t, store, expectedCommitID, commitID)
-
-	// XXX: confirm old commit is overwritten and we have rolled back
-	// LatestVersion
-	store = newMultiStoreWithMounts(db, types.PruneDefault)
-	err = store.LoadLatestVersion()
-	require.Nil(t, err)
-	commitID = getExpectedCommitID(store, ver+1)
-	checkStore(t, store, commitID, commitID)
 }
 
 func TestMultistoreLoadWithUpgrade(t *testing.T) {
@@ -554,7 +541,6 @@ func newMultiStoreWithModifiedMounts(db dbm.DB, pruningOpts types.PruningOptions
 func checkStore(t *testing.T, store *Store, expect, got types.CommitID) {
 	require.Equal(t, expect, got)
 	require.Equal(t, expect, store.LastCommitID())
-
 }
 
 func checkContains(t testing.TB, info []types.StoreInfo, wanted []string) {