Editorial: make references to No Popover state consistent

The name of the state is No Popover, so align with the other existing
references on linking the name of the state and lowercasing "state".

Author: foolip

source

@@ -1850,7 +1850,7 @@ a.setAttribute('href', 'https://example.com/'); // change the content attribute
    </li>
 
    <li><p>If <var>removedNode</var>'s <code data-x="attr-popover">popover</code> attribute is not in
-   the <span data-x="attr-popover-none-state">No Popover State</span>, then run the <span>hide
+   the <span data-x="attr-popover-none-state">No Popover</span> state, then run the <span>hide
    popover algorithm</span> given <var>removedNode</var>, false, false, false, and null.</p></li>
   </ol>
 
@@ -75780,7 +75780,7 @@ Demos:
     <p>The <code data-x="selector-popover-open">:popover-open</code> <span>pseudo-class</span> is
     defined to match any <span data-x="html elements">HTML element</span> whose <code
     data-x="attr-popover">popover</code> attribute is not in the <span
-    data-x="attr-popover-none-state">No Popover State</span> and whose <span>popover visibility
+    data-x="attr-popover-none-state">No Popover</span> state and whose <span>popover visibility
     state</span> is <span data-x="popover-showing-state">showing</span>.</p>
    </dd>
 
@@ -82220,7 +82220,7 @@ dictionary <dfn dictionary>CommandEventInit</dfn> : <span>EventInit</span> {
    <var>element</var>.</p></li>
 
    <li><p>If <var>element</var>'s <code data-x="attr-popover">popover</code> attribute is not in the
-   <span data-x="attr-popover-none-state">No Popover State</span>, then return
+   <span data-x="attr-popover-none-state">No Popover</span> state, then return
    <var>element</var>.</p></li>
 
    <li><p>Let <var>ancestor</var> be <var>element</var>.</p></li>
@@ -82235,7 +82235,7 @@ dictionary <dfn dictionary>CommandEventInit</dfn> : <span>EventInit</span> {
      <var>ancestor</var>.</p></li>
 
      <li><p>If <var>ancestor</var>'s <code data-x="attr-popover">popover</code> attribute is not in
-     the <span data-x="attr-popover-none-state">No Popover State</span>, then return
+     the <span data-x="attr-popover-none-state">No Popover</span> state, then return
      <var>ancestor</var>.</p></li>
     </ol>
    </li>