Fix key matching (need to match whole key)

src/Updater/CronUpdater.php

@@ -32,7 +32,7 @@ private function updateContent(Cron $cron, string $key): string
         $content = $this->cronManipulator->getContent();
 
         $count = 0;
-        $pattern = '/\r?\n' . $this->beginKey($key) . '.*?' . self::KEY_END . '/s';
+        $pattern = '/\r?\n' . $this->beginKey($key) . '\r?\n.*?' . self::KEY_END . '/s';
         $replacedContent = \preg_replace($pattern, $this->wrapInKey($cron, $key), $content, -1, $count);
 
         if ($count > 0) {

tests/Updater/CronUpdaterTest.php

@@ -101,6 +101,42 @@ public function shouldReplaceKeyIfExist(): void
 foo
 # END
 
+CRON;
+
+        $this->assertEquals($expectedCron, $this->manipulatorStub->contents);
+    }
+
+    /**
+     * @test
+     */
+    public function shouldReplaceExactKeyOnly(): void
+    {
+        $this->manipulatorStub->contents = <<<CRON
+headers
+# KEY key1
+value 1
+# END
+no key
+# KEY key12
+value 12
+# END
+
+CRON;
+
+        $cron = new Cron();
+        $cron->comment('replace');
+        $this->updater->updateWith($cron, 'key1');
+
+        $expectedCron = <<<CRON
+headers
+# KEY key1
+#replace
+# END
+no key
+# KEY key12
+value 12
+# END
+
 CRON;
 
         $this->assertEquals($expectedCron, $this->manipulatorStub->contents);