Correct Font Size Calculated by MsDoc Reader

Fix PHPOffice#2526. Most of that issue has already been fixed. The one remaining problem was a deprecation message handling font size. The code used `dechex($operand / 2)`, and issued the deprecation message whenever `$operand` was odd because `dechex` is designed only for integer conversion. `$operand` is actually 2 times the point size, so it will be odd only when the point size is some integer plus half a point (no other fractions are allowed). At any rate, it seems that `dechex` should not be used here in the first place; font size is a numeric value, not a hex string.

There are many problems with MsDoc Reader at the moment. This PR is narrowly focused on the problem at hand. Its test is, at least, more detailed than the existing MsDoc Reader test, which does nothing more than confirm that read successfully creates a PhpWord object. The new test verifies that the font size is as expected, but does not validate any other aspect of the read.

src/PhpWord/Reader/MsDoc.php

@@ -1871,7 +1871,7 @@ private function readPrl($data, $pos, $cbNum)
                             break;
                             // sprmCHps
                         case 0x43:
-                            $oStylePrl->styleFont['size'] = dechex($operand / 2);
+                            $oStylePrl->styleFont['size'] = $operand / 2;
 
                             break;
                             // sprmCIss

tests/PhpWordTests/Reader/MsDocTest.php

@@ -60,6 +60,22 @@ public function testLoad(): void
         self::assertInstanceOf('PhpOffice\\PhpWord\\PhpWord', $phpWord);
     }
 
+    public function testLoadHalfPointFont(): void
+    {
+        $filename = __DIR__ . '/../_files/documents/word.2526.doc';
+        $phpWord = IOFactory::load($filename, 'MsDoc');
+        $sections = $phpWord->getSections();
+        self::assertCount(1, $sections);
+        $elements = $sections[0]->getElements();
+        self::assertArrayHasKey(0, $elements);
+        $element0 = $elements[0];
+        if (method_exists($element0, 'getFontStyle')) {
+            self::assertSame(19.5, $element0->getFontStyle()->getSize());
+        } else {
+            self::fail('Unexpected no font style for first element');
+        }
+    }
+
     /**
      * Test exception on not existing file.
      */