Unify execution layer endpoints (#3214)

## Issue Addressed

Resolves #3069 

## Proposed Changes

Unify the `eth1-endpoints` and `execution-endpoints` flags in a backwards compatible way as described in https://github.com/sigp/lighthouse/issues/3069#issuecomment-1134219221

Users have 2 options:
1. Use multiple non auth execution endpoints for deposit processing pre-merge
2. Use a single jwt authenticated execution endpoint for both execution layer and deposit processing post merge

Related https://github.com/sigp/lighthouse/issues/3118

To enable jwt authenticated deposit processing, this PR removes the calls to `net_version` as the `net` namespace is not exposed in the auth server in execution clients. 
Moving away from using `networkId` is a good step in my opinion as it doesn't provide us with any added guarantees over `chainId`. See https://github.com/ethereum/consensus-specs/issues/2163 and https://github.com/sigp/lighthouse/issues/2115


Co-authored-by: Paul Hauner <paul@paulhauner.com>

scripts/local_testnet/ganache_test_node.sh

@@ -11,5 +11,4 @@ exec ganache \
 	--mnemonic "$ETH1_NETWORK_MNEMONIC" \
 	--port 8545 \
 	--blockTime $SECONDS_PER_ETH1_BLOCK \
-	--networkId "$NETWORK_ID" \
-	--chain.chainId "$NETWORK_ID"
+	--chain.chainId "$CHAIN_ID"

scripts/local_testnet/setup.sh

@@ -32,7 +32,7 @@ lcli \
 	--genesis-delay $GENESIS_DELAY \
 	--genesis-fork-version $GENESIS_FORK_VERSION \
 	--altair-fork-epoch $ALTAIR_FORK_EPOCH \
-	--eth1-id $NETWORK_ID \
+	--eth1-id $CHAIN_ID \
 	--eth1-follow-distance 1 \
 	--seconds-per-slot $SECONDS_PER_SLOT \
 	--seconds-per-eth1-block $SECONDS_PER_ETH1_BLOCK \

scripts/local_testnet/vars.env

@@ -30,7 +30,7 @@ GENESIS_DELAY=0
 BOOTNODE_PORT=4242
 
 # Network ID and Chain ID of local eth1 test network
-NETWORK_ID=4242
+CHAIN_ID=4242
 
 # Hard fork configuration
 ALTAIR_FORK_EPOCH=18446744073709551615

scripts/tests/vars.env

@@ -30,7 +30,7 @@ GENESIS_DELAY=0
 BOOTNODE_PORT=4242
 
 # Network ID and Chain ID of local eth1 test network
-NETWORK_ID=4242
+CHAIN_ID=4242
 
 # Hard fork configuration
 ALTAIR_FORK_EPOCH=18446744073709551615