Support unprotected txs

[mdehoog]

Description

There is a flag for enabling pre-EIP-155 transactions:

ethermint/server/flags/flags.go

Line 65 in 07cf2bd

JSONRPCAllowUnprotectedTxs = "json-rpc.allow-unprotected-txs"

Currently that flag is not read when creating the configuration, which this PR fixes.

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[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days-before-close if no further activity occurs.

[mdehoog]

cc @Vvaradinov @MalteHerrmann