…python#5460)

Ref: python/cpython#5460
Ref: https://bugs.python.org/issue25988

Ref: python/cpython#5460
Ref: https://bugs.python.org/issue25988

Fix DeprecationWarning from classes in collections.abc

This patch removes the following warning:
```
/usr/share/nvim/runtime/third_party/ycmd/ycmd/utils.py:499: DeprecationWarning: Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated, and in 3.8 it will stop working
  class HashableDict( collections.Mapping ):
```
This warning is originated from python/cpython#5460

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This PR stops using the following deprecated functions in std Python lib.

* parser.readfp
  We should use parser.read_file(readline_generator(fp))[1].
* importing modules from collections directly.
  We should use collections.abc instead of using collections directly.[2]

--
[1]: https://docs.python.org/3/library/configparser.html#configparser.ConfigParser.readfp
[2]: python/cpython#5460

Task: 44767
Story: 2009917
Change-Id: I61bf4299ad2acd8ee26b4aab66875b10287020e1

* Update trove from branch 'master'
  to 04e85c1be0732b7f9333468723b1e1b26d6ddc02
  - Merge "Stop using deprecated functions in std Python lib"
  - Stop using deprecated functions in std Python lib
    
    This PR stops using the following deprecated functions in std Python lib.
    
    * parser.readfp
      We should use parser.read_file(readline_generator(fp))[1].
    * importing modules from collections directly.
      We should use collections.abc instead of using collections directly.[2]
    
    --
    [1]: https://docs.python.org/3/library/configparser.html#configparser.ConfigParser.readfp
    [2]: python/cpython#5460
    
    Task: 44767
    Story: 2009917
    Change-Id: I61bf4299ad2acd8ee26b4aab66875b10287020e1