Disallow invalid inline style comments in stylesheets (#9099)

res/css/views/toasts/_IncomingCallToast.pcss

@@ -18,7 +18,7 @@ limitations under the License.
 .mx_IncomingCallToast {
     display: flex;
     flex-direction: row;
-    pointer-events: initial; // restore pointer events so the user can accept/decline
+    pointer-events: initial; /* restore pointer events so the user can accept/decline */
 
     .mx_IncomingCallToast_content {
         display: flex;

res/css/views/toasts/_NonUrgentEchoFailureToast.pcss

@@ -22,12 +22,12 @@ limitations under the License.
         mask-position: center;
         mask-size: contain;
         mask-repeat: no-repeat;
-        background-color: #fff; // we know that non-urgent toasts are always styled the same
+        background-color: #fff; /* we know that non-urgent toasts are always styled the same */
         mask-image: url('$(res)/img/element-icons/cloud-off.svg');
         margin-right: 8px;
     }
 
-    span { // includes the i18n block
+    span { /* includes the i18n block */
         vertical-align: middle;
     }
 }