Update code coverage badge

Author: github-actions[bot]

clover.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<coverage generated="1611785096">
-  <project timestamp="1611785096">
+<coverage generated="1611785904">
+  <project timestamp="1611785904">
     <file name="/home/runner/work/phpunit-coverage-badge/phpunit-coverage-badge/src/BadgeGenerator.php">
       <class name="PhpUnitCoverageBadge\BadgeGenerator" namespace="global">
         <metrics complexity="7" methods="4" coveredmethods="4" conditionals="0" coveredconditionals="0" statements="19" coveredstatements="19" elements="23" coveredelements="23"/>