Feature Description

#730 introduced PhpStan and started with level 0 conformance. Now we can increase the rule level to further improve the codebase.

Once this is resolved, another issue should be created to bump the rule level again.

• Improve static analysis in Performance Lab plugin files #1188
• Fix PHPStan issues in Optimization Detective #1195
• Update PHPStan level to 1 #1198
• Update PHPStan level to 2 #1199
• Update PHPStan level to 3 #1200
• Update PHPStan level to 4 #1201
• Update PHPStan level to 5 #1202
• Update PHPStan level to 6 #1203
• Update PHPStan level to 7 #1205
• Update PHPStan level to 8 #1210
• Add PHPStan strict rules (except for empty.notAllowed) #1241
• Update PHPStan level to 9 (maybe) #1211 (maybe not)
• PHPStan errors being ignored should specify the error identifiers #1209