CI: Fix calculating diff between branches in PRs (#7973)

Make Mess Detector working again™️

.github/workflows/sca.yml

@@ -29,6 +29,13 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v4
 
+      # We need to fetch base branch because `actions/checkout` only initializes empty repo and fetches PR's meta-branch
+      # which leads to `fatal: ambiguous argument 'origin/...': unknown revision or path not in the working tree.`,
+      # because of that `CHANGED_PHP_FILES` is not set, and tools based on diff between branches (like Mess Detector) don't work.
+      - name: Fetch base branch
+        if: ${{ github.event_name == 'pull_request' }}
+        run: git fetch --no-tags --prune --no-recurse-submodules --depth=1 origin $GITHUB_BASE_REF
+
       - name: Setup PHP with Composer deps
         uses: ./.github/composite-actions/setup-php-with-composer-deps
         with:

phpstan.dist.neon

@@ -55,6 +55,6 @@ parameters:
         -
             message: '#^Method PhpCsFixer\\Tests\\.+::provide.+Cases\(\) return type has no value type specified in iterable type iterable\.$#'
             path: tests
-            count: 1017
+            count: 1014
     tipsOfTheDay: false
     tmpDir: dev-tools/phpstan/cache

tests/Fixer/ClassNotation/FinalClassFixerTest.php

@@ -33,6 +33,9 @@ public function testFix(string $expected, ?string $input = null): void
         $this->doTest($expected, $input);
     }
 
+    /**
+     * @return iterable<array{0: string, 1?: string}>
+     */
     public static function provideFixCases(): iterable
     {
         yield ['<?php /** @Entity */ class MyEntity {}'];
@@ -104,6 +107,9 @@ public function testFix80(string $expected, ?string $input = null): void
         $this->doTest($expected, $input);
     }
 
+    /**
+     * @return iterable<array{0: string, 1?: string}>
+     */
     public static function provideFix80Cases(): iterable
     {
         yield ['<?php #[Entity] class MyEntity {}'];
@@ -207,6 +213,9 @@ public function testFix82(string $expected, ?string $input = null): void
         $this->doTest($expected, $input);
     }
 
+    /**
+     * @return iterable<array{0: string, 1?: string}>
+     */
     public static function provideFix82Cases(): iterable
     {
         yield ['<?php #[Entity] readonly class MyEntity {}'];