fix: add pagination flags to token-pairs query

[mmsqe]

Description

for test info

---

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• tackled an existing issue or discussed with a team member
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[aljo242]

@vladjdk to review - do we need to check if this logic is tested in the actual grpc query?

[vladjdk]

@aljo242 tested:

evm/tests/integration/x/erc20/test_grpc_query.go

Lines 40 to 57 in 369defb

	{
	"1 pair registered w/pagination",
	func() {
	req = &types.QueryTokenPairsRequest{
	Pagination: &query.PageRequest{Limit: 10, CountTotal: true},
	}
	pairs := testconstants.ExampleTokenPairs
	pair := types.NewTokenPair(utiltx.GenerateAddress(), "coin", types.OWNER_MODULE)
	s.network.App.GetErc20Keeper().SetTokenPair(ctx, pair)
	pairs = append(pairs, pair)
	expRes = &types.QueryTokenPairsResponse{
	Pagination: &query.PageResponse{Total: uint64(len(pairs))},
	TokenPairs: pairs,
	}
	},
	true,
	},

[vladjdk]

lgtm, thanks!