Monitor transaction submitted for execution

[elgatovital]

Handles #1987

Changes proposed in this pull request:

• Persist tx data submitted to execution locally
• Get tx receipt and update tx status to pending if it was not yet indexed

@gnosis/mobile-devs

[elgatovital]

Please add tests for the new repository

Edit: Also a couple view models have new logic which should also be tested

yes, already have task for it https://github.com/safe-global/safe-android/issues/1963

[rmeissner]

We should not merge new logic without tests. It makes little sense to do the tests in a separate PR :thinking: