Skip gas estimation if already present (ethereum)

[korkoshko]

Description

We don't need call estimateGas if the gas property already present in the serialized transaction.

Type of change

• [x] Bug fix (non-breaking change which fixes an issue)

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes
• [ ] Any dependent changes have been merged and published in downstream modules

[korkoshko]

@Hathoriel could you please review this?

[Hathoriel]

Hello @korkoshko Thank you for your PR. It looks perfect, but can you please upgrade the package.json version? After you do it, I will approve and merge this pull request. Thank you

[korkoshko]

@Hathoriel Done. Thanks!