l2geth: update readme

[tynes]

Description
Simply update the readme to make local development with l2geth easier

[changeset-bot]

⚠️ No Changeset found

Latest commit: e56e0a5

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[codecov-commenter]

Codecov Report

Merging #2120 (8a2f7b2) into develop (40ffd24) will increase coverage by 3.97%.
The diff coverage is n/a.

❗ Current head 8a2f7b2 differs from pull request most recent head e56e0a5. Consider uploading reports for the commit e56e0a5 to get more accurate results

@@             Coverage Diff             @@
##           develop    #2120      +/-   ##
===========================================
+ Coverage    73.37%   77.35%   +3.97%     
===========================================
  Files           85       57      -28     
  Lines         2836     1983     -853     
  Branches       464      292     -172     
===========================================
- Hits          2081     1534     -547     
+ Misses         755      449     -306     

Flag	Coverage Δ
batch-submitter	62.63% <ø> (ø)
contracts	90.48% <ø> (ø)
core-utils	59.94% <ø> (ø)
data-transport-layer	?
message-relayer	?
sdk	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
packages/sdk/src/cross-chain-messenger.ts
packages/message-relayer/hardhat.config.ts
packages/sdk/hardhat.config.ts
packages/sdk/src/adapters/eth-bridge.ts
...layer/src/services/l1-ingestion/handlers/errors.ts
packages/sdk/src/utils/misc-utils.ts
packages/sdk/src/adapters/dai-bridge.ts
packages/data-transport-layer/src/utils/common.ts
packages/data-transport-layer/src/utils/index.ts
...kages/data-transport-layer/src/utils/validation.ts
... and 18 more

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