Remove redundant lambda around cleanup code (#8192)

Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>

beacon-chain/core/blocks/deposit_test.go

@@ -277,9 +277,7 @@ func TestPreGenesisDeposits_SkipInvalidDeposit(t *testing.T) {
 	testutil.ResetCache()
 	dep, _, err := testutil.DeterministicDepositsAndKeys(100)
 	require.NoError(t, err)
-	defer func() {
-		testutil.ResetCache()
-	}()
+	defer testutil.ResetCache()
 	dep[0].Data.Signature = make([]byte, 96)
 	trie, _, err := testutil.DepositTrieFromDeposits(dep)
 	require.NoError(t, err)

beacon-chain/powchain/service_test.go

@@ -298,9 +298,7 @@ func TestFollowBlock_OK(t *testing.T) {
 	conf := params.BeaconConfig()
 	conf.SecondsPerETH1Block = 10
 	params.OverrideBeaconConfig(conf)
-	defer func() {
-		params.UseMainnetConfig()
-	}()
+	defer params.UseMainnetConfig()
 
 	web3Service = setDefaultMocks(web3Service)
 	web3Service.eth1DataFetcher = &goodFetcher{backend: testAcc.Backend}
@@ -470,9 +468,7 @@ func TestNewService_EarliestVotingBlock(t *testing.T) {
 	conf.SecondsPerETH1Block = 10
 	conf.Eth1FollowDistance = 50
 	params.OverrideBeaconConfig(conf)
-	defer func() {
-		params.UseMainnetConfig()
-	}()
+	defer params.UseMainnetConfig()
 
 	// Genesis not set
 	followBlock := uint64(2000)