Fixing build by setting stubs ver. to older ver.

[CodyWilson]

phpstorm-stubs dev-master already had PHP8 features which are breaking
the parser per #795.
The simple solution for this is to force an older version of the stubs.

[CodyWilson]

As a note, the appveyor build failing appears to be due to updates to microsoft/tolerant-php-parser.
Which also isn't really controlled well for versions, then again they're just sticking all changes in 0.0 and not iterating for anything that could be considered a breaking change.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.12%. Comparing base (9dc1656) to head (cb66104).

Additional details and impacted files

@@            Coverage Diff            @@
##             master     #797   +/-   ##
=========================================
  Coverage     82.12%   82.12%           
  Complexity      935      935           
=========================================
  Files            44       44           
  Lines          2154     2154           
=========================================
  Hits           1769     1769           
  Misses          385      385           

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