Bump web3 from 5.11.0 to 5.20.1 in /requirements

[dependabot]

Bumps web3 from 5.11.0 to 5.20.1.

Changelog

Sourced from web3's changelog.

v5.20.1 (2021-07-01)

Web3 5.20.1 (2021-07-01)

Bugfixes

- Have the geth dev IPC auto connection check for the ``WEB3_PROVIDER_URI`` environment variable. (`[#2023](https://github.com/ethereum/web3.py/issues/2023) <https://github.com/ethereum/web3.py/issues/2023>`__)
Improved Documentation

• Remove reference to allowing multiple providers in docs ([#2018](https://github.com/ethereum/web3.py/issues/2018) <https://github.com/ethereum/web3.py/issues/2018>__)
• Update "Contract Deployment Example" docs to use py-solc-x as solc is no longer maintained. ([#2020](https://github.com/ethereum/web3.py/issues/2020) <https://github.com/ethereum/web3.py/issues/2020>__)
• Detail using unreleased Geth builds in CI ([#2037](https://github.com/ethereum/web3.py/issues/2037) <https://github.com/ethereum/web3.py/issues/2037>__)
• Clarify that a missing trie node error could occur when using block_identifier with .call() on a node that isn't running in archive mode ([#2048](https://github.com/ethereum/web3.py/issues/2048) <https://github.com/ethereum/web3.py/issues/2048>__)

Misc

- `[#1938](https://github.com/ethereum/web3.py/issues/1938) <https://github.com/ethereum/web3.py/issues/1938>`__, `[#2015](https://github.com/ethereum/web3.py/issues/2015) <https://github.com/ethereum/web3.py/issues/2015>`__, `[#2021](https://github.com/ethereum/web3.py/issues/2021) <https://github.com/ethereum/web3.py/issues/2021>`__, `[#2025](https://github.com/ethereum/web3.py/issues/2025) <https://github.com/ethereum/web3.py/issues/2025>`__, `[#2028](https://github.com/ethereum/web3.py/issues/2028) <https://github.com/ethereum/web3.py/issues/2028>`__, `[#2029](https://github.com/ethereum/web3.py/issues/2029) <https://github.com/ethereum/web3.py/issues/2029>`__, `[#2035](https://github.com/ethereum/web3.py/issues/2035) <https://github.com/ethereum/web3.py/issues/2035>`__
v5.20.0 (2021-06-09)
Web3 5.20.0 (2021-06-09)
Features

• Add new AsyncHTTPProvider. No middleware or session caching support yet.

  Also adds async w3.eth.gas_price, and async w3.isConnected() methods. ([#1978](https://github.com/ethereum/web3.py/issues/1978) <https://github.com/ethereum/web3.py/issues/1978>__)

• Add ability for AsyncHTTPProvider to accept middleware

  Also adds async gas_price_strategy middleware, and moves gas estimate to middleware.

  AsyncEthereumTesterProvider now inherits from AsyncBase ([#1999](https://github.com/ethereum/web3.py/issues/1999) <https://github.com/ethereum/web3.py/issues/1999>__)

• Support state_override in contract function call. ([#2005](https://github.com/ethereum/web3.py/issues/2005) <https://github.com/ethereum/web3.py/issues/2005>__)

Bugfixes

- Test ethpm caching + bump Sphinx version. (`[#1977](https://github.com/ethereum/web3.py/issues/1977) <https://github.com/ethereum/web3.py/issues/1977>`__)
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Commits

• f13d78a Bump version: 5.20.0 → 5.20.1
• f526eb8 Compile release notes
• b396144 Clarify that using block_identifier with .call() comes with its caveats (#2...
• 5f83154 Upgrade websockets to >=9.1.0 (#2029)
• 3630f11 Remove unused middleware (#2015)
• e152999 support unreleased Geth builds in CI (#2037)
• b4f9336 bump Geth fixture to v1.10.4 (#2035)
• 588e0c0 (closes #2020) Update the contract deployment docs to use py-solc-x.
• f4add46 Honor WEB3_PROVIDER_URI for geth auto dev connection (#2023)
• d7ae2df Add news fragment for updating to flaky version >=3.7.0,<4
• Additional commits viewable in compare view

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[dependabot]

Superseded by #45.