chore(ampd): make default gas adjustment 1.2 to increase chance of broadcast sucess

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 93.56%. Comparing base (05579e6) to head (c5947a5). Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #636 +/- ## ======================================= Coverage 93.56% 93.56% ======================================= Files 241 241 Lines 33954 33954 ======================================= Hits 31768 31768 Misses 2186 2186 ``` | [Flag](https://app.codecov.io/gh/axelarnetwork/axelar-amplifier/pull/636/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=axelarnetwork) | Coverage Δ | | |---|---|---| | [](https://app.codecov.io/gh/axelarnetwork/axelar-amplifier/pull/636/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=axelarnetwork) | `93.56% <100.00%> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=axelarnetwork#carryforward-flags-in-the-pull-request-comment) to find out more.

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.