fix golangcli-lint complaint (#2463) (#2476)

## Description

closes: #XXXX

---

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- [x] Targeted PR against correct branch (see [CONTRIBUTING.md](https://github.com/cosmos/ibc-go/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
- [ ] Code follows the [module structure standards](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules/structure.md).
- [ ] Wrote unit and integration [tests](https://github.com/cosmos/ibc-go/blob/master/CONTRIBUTING.md#testing)
- [ ] Updated relevant documentation (`docs/`) or specification (`x/<module>/spec/`)
- [ ] Added relevant `godoc` [comments](https://blog.golang.org/godoc-documenting-go-code).
- [ ] Added a relevant changelog entry to the `Unreleased` section in `CHANGELOG.md`
- [x] Re-reviewed `Files changed` in the Github PR explorer
- [ ] Review `Codecov Report` in the comment section below once CI passes

(cherry picked from commit 503b9eb)

Co-authored-by: Carlos Rodriguez <carlos@interchain.io>

modules/core/23-commitment/types/merkle.go

@@ -271,8 +271,10 @@ func verifyChainedMembershipProof(root []byte, specs []*ics23.ProofSpec, proofs
 
 // blankMerkleProof and blankProofOps will be used to compare against their zero values,
 // and are declared as globals to avoid having to unnecessarily re-allocate on every comparison.
-var blankMerkleProof = &MerkleProof{}
-var blankProofOps = &tmcrypto.ProofOps{}
+var (
+	blankMerkleProof = &MerkleProof{}
+	blankProofOps    = &tmcrypto.ProofOps{}
+)
 
 // Empty returns true if the root is empty
 func (proof *MerkleProof) Empty() bool {