minor #49936 [DependencyInjection] Add more precise types in EnvVarProcessorInterface (stof)

This PR was merged into the 6.3 branch.

Discussion
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[DependencyInjection] Add more precise types in `EnvVarProcessorInterface`

| Q             | A
| ------------- | ---
| Branch?       | 6.3
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Tickets       | n/a
| License       | MIT
| Doc PR        | n/a

This more precise type will help static analyzers and IDEs to spot mistakes in implementations of this interface

Commits
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9fb701dfe1 Add more precise types in EnvVarProcessorInterface

Author: fabpot

EnvVarProcessorInterface.php

@@ -23,16 +23,16 @@ interface EnvVarProcessorInterface
     /**
      * Returns the value of the given variable as managed by the current instance.
      *
-     * @param string   $prefix The namespace of the variable
-     * @param string   $name   The name of the variable within the namespace
-     * @param \Closure $getEnv A closure that allows fetching more env vars
+     * @param string                  $prefix The namespace of the variable
+     * @param string                  $name   The name of the variable within the namespace
+     * @param \Closure(string): mixed $getEnv A closure that allows fetching more env vars
      *
      * @throws RuntimeException on error
      */
     public function getEnv(string $prefix, string $name, \Closure $getEnv): mixed;
 
     /**
-     * @return string[] The PHP-types managed by getEnv(), keyed by prefixes
+     * @return array<string, string> The PHP-types managed by getEnv(), keyed by prefixes
      */
     public static function getProvidedTypes(): array;
 }