Remove linebreak in URL to referenced Android commit

This URL was spotted as broken by a tool I'm creating for checking www.mozilla.org. I've removed the linebreak and confirmed via the Preview tab that it still works.

announce/2015/mfsa2015-147.md

@@ -28,8 +28,7 @@ Thunderbird product, but is potentially a risk in browser or browser-like contex
 (<a href="http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-7222"
 class="ex-ref">CVE-2015-7222</a>)</li>
    <li><a
-href="https://android.googlesource.com/platform/frameworks/av/+/
-c87faed60483afb2466e03892bda80b72e5822c7%5E!/#F0">Fix integer underflow in covr MPEG4
+href="https://android.googlesource.com/platform/frameworks/av/+/c87faed60483afb2466e03892bda80b72e5822c7%5E!/#F0">Fix integer underflow in covr MPEG4
 processing</a></li>
 </ul>