Remove </input> tag in animation.HTMLWriter

HTML `<input>` tags are not closed by `</input>`, including it causes some HTML parsers to fail.

Author: tttapa

lib/matplotlib/_animation_data.py

@@ -196,7 +196,7 @@
   <div class="anim-controls">
     <input id="_anim_slider{id}" type="range" class="anim-slider"
            name="points" min="0" max="1" step="1" value="0"
-           oninput="anim{id}.set_frame(parseInt(this.value));"></input>
+           oninput="anim{id}.set_frame(parseInt(this.value));">
     <div class="anim-buttons">
       <button title="Decrease speed" aria-label="Decrease speed" onclick="anim{id}.slower()">
           <i class="fa fa-minus"></i></button>