Fix: Add missing alt attributes to F-Droid images in languages page

This commit addresses an HTMLProofer error where F-Droid images were missing alt attributes when a language pack didn't have an F-Droid link.

The alt attribute 'F-Droid icon' has been added to these images.

Additionally, a minor typo in the Google Play Store link condition (ni -> nil and ""l -> "") has been corrected.

Author: google-labs-jules[bot]

languages.html

@@ -15,12 +15,12 @@
 	{% endif %}
 
 	{% if language.f-droid == nil or language.f-droid == "" %}
-	<img class="no-link-found not-full-icon" src="/images/fdroid.png" width="32px" height="32px"/></a>
+	<img class="no-link-found not-full-icon" src="/images/fdroid.png" width="32px" height="32px" alt="F-Droid icon"/></a>
 	{% else %}
 	<a href="{{ language.f-droid }}"><img class="not-full-icon" src="/images/fdroid.png" alt="{{ language.name }} on f-droid" width="32px" height="32px"/></a>
 	{% endif %}
 
-	{% if language.play == ni or language.play == ""l %}
+	{% if language.play == nil or language.play == "" %}
 	<img class="no-link-found not-full-icon" src="/images/play.png" width="32px" height="32px"/></a>
 	{% else %}
 	<a href="{{ language.play }}"><img class="not-full-icon" src="/images/play.png" alt="{{ language.name }} on Google Play Store" width="32px" height="32px"/></a>