Fix: Don't reload page on search form submits

Both file search and plugin repository search reloaded the page when
hitting enter in the search field. This fixes that.

src/octoprint/plugins/pluginmanager/static/js/pluginmanager.js

@@ -147,7 +147,11 @@ $(function() {
             }
         });
 
-        self.performRepositorySearch = function() {
+        self.performRepositorySearch = function(e) {
+            if (e !== undefined) {
+                e.preventDefault();
+            }
+
             var query = self.repositorySearchQuery();
             if (query !== undefined && query.trim() != "") {
                 self.repositoryplugins.changeSearchFunction(function(entry) {

src/octoprint/plugins/pluginmanager/templates/pluginmanager_settings.jinja2

@@ -83,7 +83,7 @@
             </a>
         </h4>
 
-        <form class="form-search">
+        <form class="form-search" data-bind="submit: performRepositorySearch">
             <input type="text" class="input-block search-query" data-bind="value: repositorySearchQuery, valueUpdate: 'input'" placeholder="{{ _('Search...') }}">
         </form>
 

src/octoprint/static/js/app/viewmodels/files.js

@@ -308,7 +308,11 @@ $(function() {
             return output;
         };
 
-        self.performSearch = function() {
+        self.performSearch = function(e) {
+            if (e !== undefined) {
+                e.preventDefault();
+            }
+
             var query = self.searchQuery();
             if (query !== undefined && query.trim() != "") {
                 self.listHelper.changeSearchFunction(function(entry) {

src/octoprint/templates/sidebar/files.jinja2

@@ -1,4 +1,4 @@
-<form class="form-search">
+<form class="form-search" data-bind="submit: performSearch">
     <input type="text" class="input-block search-query" data-bind="value: searchQuery, valueUpdate: 'input'" placeholder="{{ _('Search...') }}">
 </form>
 <div class="gcode_files" data-bind="slimScrolledForeach: listHelper.paginatedItems">