Build(deps-dev): Update phpstan/phpstan requirement from ^0.12.8 to ^0.12.9

[dependabot-preview]

Updates the requirements on phpstan/phpstan to permit the latest version.

Release notes

Sourced from phpstan/phpstan's releases.

0.12.9

Major new features 🚀

Support for custom type aliases (phpstan/phpstan-src@3151160)

Type aliases (also known as typedef) are a popular feature in other languages like TypeScript or C++. Using the following configuration in phpstan.neon will allow you to reference these types in your PHPDocs:

parameters:
    typeAliases:
        Name: 'string'
        NameResolver: 'callable(): string'
        NameOrResolver: 'Name|NameResolver'

/**
 * @param NameOrResolver $arg
 */
function foo($arg)
{
    // $arg is string|(callable(): string)
}

Several performance optimizations - you should see performance improvements between 10–20%:

• Memoizing dependency injection container (phpstan/phpstan-src@3eb84e2), #2915
• add memoize cache on ClassReflection::isGeneric() (#115), thanks @bastnic!
• Cache calls to prettyPrintExpr in MutatingScope (#122), thanks @bastnic!

Improvements 🔧

• Possibly-wrong "cannot access offset" should be reported on level 7, not level 3 (phpstan/phpstan-src@c36df00)
• Ignored error regex with unescaped '||' is an unavoidable error (phpstan/phpstan-src@3b71993)

Bugfixes 🐛

• Threaded (pthreads) objects have array syntax support without ArrayAccess (#116), thanks @dktapps!
• Fix issue with PHAR when the analysed projects also includes jetbrains/phpstorm-stubs (phpstan/phpstan-src@49314cb), #2938
• Invalidate json_last_error{,_msg}() type on json_{en,de}code() call (#118), thanks @cs278!
• FileCacheStorage - atomic save() (phpstan/phpstan-src@65118a2, phpstan/phpstan-src@a672c89)

Function signature fixes 🤖

... (truncated)

Commits

• 297cb24 PHPStan 0.12.9
• 08f1998 E2E test for project with react/promise and parallel run
• 81cd8f4 Updated PHPStan to commit 252e81454a09917a690fe97b5f3d6a31457e157e
• 288582b Updated PHPStan to commit 794c491159b50b7a8442cc032f61d21632b495bb
• 013442e Updated PHPStan to commit e59bcf55e3aefbe4318eeec9f558c92f3ae2f5e5
• d173f7e Fix build
• 8bbb015 Autoloader bootstrap - save memory
• 2b6ca1b Updated PHPStan to commit b84acd2e3eadf66189a64fdbc6dd18ff76323f67
• 1f36c4b Updated PHPStan to commit 7fe02c9f177fbc33551a1bc6f575fd47305930d4
• 3b3679a TMP - skip updating playground
• Additional commits viewable in compare view

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[codecov-io]

Codecov Report

Merging #305 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##             master    #305   +/-   ##
========================================
  Coverage      40.9%   40.9%           
  Complexity      303     303           
========================================
  Files            27      27           
  Lines           929     929           
========================================
  Hits            380     380           
  Misses          549     549

Flag	Coverage Δ	Complexity Δ
#phpunit	40.9% <ø> (ø)	303 <ø> (ø)	⬇️

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