deps: Update dependency urllib3 to v1.26.16

[renovate-bot]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
urllib3 (changelog)	==1.26.12 -> ==1.26.16

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Release Notes

urllib3/urllib3 (urllib3)

v1.26.16

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• Fixed thread-safety issue where accessing a PoolManager with many distinct origins
  would cause connection pools to be closed while requests are in progress (#&#8203;2954 <https://github.com/urllib3/urllib3/pull/2954>_)

v1.26.15

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• Fix socket timeout value when HTTPConnection is reused (#&#8203;2645 <https://github.com/urllib3/urllib3/issues/2645>__)
• Remove "!" character from the unreserved characters in IPv6 Zone ID parsing
  (#&#8203;2899 <https://github.com/urllib3/urllib3/issues/2899>__)
• Fix IDNA handling of '\x80' byte (#&#8203;2901 <https://github.com/urllib3/urllib3/issues/2901>__)

v1.26.14

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• Fixed parsing of port 0 (zero) returning None, instead of 0. (#&#8203;2850 <https://github.com/urllib3/urllib3/issues/2850>__)
• Removed deprecated getheaders() calls in contrib module. Fixed the type hint of PoolKey.key_retries by adding bool to the union. (#&#8203;2865 <https://github.com/urllib3/urllib3/issues/2865>__)

v1.26.13

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• Deprecated the HTTPResponse.getheaders() and HTTPResponse.getheader() methods.
• Fixed an issue where parsing a URL with leading zeroes in the port would be rejected
  even when the port number after removing the zeroes was valid.
• Fixed a deprecation warning when using cryptography v39.0.0.
• Removed the <4 in the Requires-Python packaging metadata field.

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