[CLEANUP] Rector: Add return type from strict return type of call

This applies the rule ReturnTypeFromStrictTypedCallRector. For
Details see:
https://github.com/rectorphp/rector/blob/main/docs/rector_rules_overview.md#returntypefromstricttypedcallrector

Signed-off-by: Daniel Ziegenberg <[email protected]>

Author: ziegenberg

src/Parser.php

@@ -51,11 +51,9 @@ public function getCharset(): void
     /**
      * Parses the CSS provided to the constructor and creates a `Document` from it.
      *
-     * @return Document
-     *
      * @throws SourceException
      */
-    public function parse()
+    public function parse(): Document
     {
         return Document::parse($this->oParserState);
     }

src/Parsing/ParserState.php

@@ -308,12 +308,10 @@ public function consume($mValue = 1): string
      * @param string $mExpression
      * @param int|null $iMaxLength
      *
-     * @return string
-     *
      * @throws UnexpectedEOFException
      * @throws UnexpectedTokenException
      */
-    public function consumeExpression($mExpression, $iMaxLength = null)
+    public function consumeExpression($mExpression, $iMaxLength = null): string
     {
         $aMatches = null;
         $sInput = $iMaxLength !== null ? $this->peek($iMaxLength) : $this->inputLeft();