Prepare for 0.9.0 release

[BurnzZ]

TODO after merge:

• Change YYYY-MM-DD in CHANGELOG to actual date
• Tag 0.9.0 and push

List of changes:

• Supporting to_return in web-poet rules #88
• Don't put microseconds into frozen_time. #122
• doc improvements #121
• fix failing tests after new warning phrases for dupe rules #125
• Default: SCRAPY_POET_RULES = web_poet.default_registry.get_rules() #120
• Fix CI failing on min, asyncio, and asyncio-min envs #129
• officially support scrapy.http.request.NO_CALLBACK on scrapy>=2.8 #126

There's no change that warrants the need for a new web-poet version to be used.

[codecov]

Codecov Report

Merging #131 (7253cd4) into master (db465bb) will not change coverage.
The diff coverage is n/a.

❗ Current head 7253cd4 differs from pull request most recent head ec5075c. Consider uploading reports for the commit ec5075c to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #131   +/-   ##
=======================================
  Coverage   89.25%   89.25%           
=======================================
  Files          14       14           
  Lines         763      763           
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  Hits          681      681           
  Misses         82       82           

[kmike]

👍