Update Tokio to 1.0, Prost to 0.7 and Tonic to 0.4

[romac]

Closes: #527

Description

Update Tokio to 1.0, Prost to 0.7 and Tonic to 0.4.

Depends on informalsystems/tendermint-rs#783.

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For contributor use:

• Updated the Unreleased section of CHANGELOG.md with the issue.
• If applicable: Unit tests written, added test to CI.
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Updated relevant documentation (docs/) and code comments.
• Re-reviewed Files changed in the Github PR explorer.

[codecov-io]

Codecov Report

Merging #534 (13cb248) into master (b1b37f5) will increase coverage by 27.3%.
The diff coverage is 69.2%.

@@            Coverage Diff            @@
##           master    #534      +/-   ##
=========================================
+ Coverage    13.6%   41.0%   +27.3%     
=========================================
  Files          69     133      +64     
  Lines        3752    8315    +4563     
  Branches     1374       0    -1374     
=========================================
+ Hits          513    3415    +2902     
- Misses       2618    4900    +2282     
+ Partials      621       0     -621     

Impacted Files	Coverage Δ
...application/ics20_fungible_token_transfer/error.rs	0.0% <0.0%> (ø)
...pplication/ics20_fungible_token_transfer/events.rs	0.0% <ø> (ø)
...ion/ics20_fungible_token_transfer/msgs/transfer.rs	0.0% <0.0%> (ø)
modules/src/events.rs	0.0% <0.0%> (ø)
modules/src/ics02_client/error.rs	100.0% <ø> (ø)
modules/src/ics02_client/events.rs	0.0% <0.0%> (ø)
modules/src/ics02_client/raw.rs	0.0% <0.0%> (ø)
modules/src/ics03_connection/error.rs	100.0% <ø> (+66.6%)	⬆️
modules/src/ics03_connection/events.rs	0.0% <0.0%> (ø)
modules/src/ics04_channel/error.rs	100.0% <ø> (+75.0%)	⬆️
... and 228 more

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[ancazamfir]

Looks good! It will be interesting to see if we can move back to self.block_on() without the performance issues.