change API key edit button text (#10379)

Author: Goodyear2017

src/NuGetGallery/Views/Users/ApiKeys.cshtml

@@ -497,7 +497,7 @@
             <div class="col-sm-6 form-group">
                 <input type="submit" class="btn btn-brand btn-block"
                        data-bind="enable: SelectPackagesEnabled() && !PendingCreateOrEdit(),
-                                  attr: { value: Key() ? 'Edit' : 'Create' }" />
+                                  attr: { value: Key() ? 'Save' : 'Create' }" />
             </div>
             <div class="col-sm-6 form-group">
                 <button data-bind="attr: { 'data-target': '#' + EditContainerId(),