Handle RecoverableError in the python api's set_total_deposit

[LefterisJP]

Fix #4937

Description

Please, describe what this PR does in detail:

• If it's a bug fix, detail the root cause of the bug and how this PR fixes it.
• If it's a new feature, describe the feature this PR is introducing and design decisions.
• If it's a refactoring, describe why it is necessary. What are its pros and cons in respect to the previous code, and other possible design choices.

PR review check list

Quality check list that cannot be automatically verified.

• Safety
  • The changes respect the necessary conditions for safety (https://raiden-network-specification.readthedocs.io/en/latest/smart_contracts.html#protocol-values-constraints)
• Code quality
  • Error conditions are handled
  • Exceptions are propagated to the correct parent greenlet
  • Exceptions are correctly classified as recoverable or unrecoverable
• Compatibility
  • State changes are forward compatible
  • Transport messages are backwards and forward compatible
• Commits
  • Have good messages
  • Squashed unecessary commits
• If it's a bug fix:
  • Regression test for the bug
    • Properly covers the bug
    • If an integration test is used, it could not be written as a unit test
• Documentation
  • A new CLI flag was introduced, is there documentation that explains usage?
• Specs
  • If this is a protocol change, are the specs updated accordingly? If so, please link PR from the specs repo.
• Is it a user facing feature/bug fix?
  • Changelog entry has been added

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (develop@5a0109a). Click here to learn what that means.
The diff coverage is 80%.

@@            Coverage Diff             @@
##             develop    #4938   +/-   ##
==========================================
  Coverage           ?   80.77%           
==========================================
  Files              ?      120           
  Lines              ?    14519           
  Branches           ?     2238           
==========================================
  Hits               ?    11728           
  Misses             ?     2135           
  Partials           ?      656

Impacted Files	Coverage Δ
raiden/api/python.py	68.33% <80%> (ø)

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[LefterisJP]

Oh man come on. Changed 2 lines to catch an exception. Wrote an entire new test which recreates a race (took a bit of time as we did not have any such tests in the rest api) to trigger the bug seen in the issue ... and still the coverage is decreased?!?!

[rakanalh]

LGTM, thanks for taking this one.