Fixed blue focus-within state for sl-menu-items (#3836)

fixes #3806
<!-- Link to relevant issue (for ex: "fixes #1234") which will
automatically close the issue once the PR is merged -->

## PR Type
Bugfix

## Describe the current behavior? + Describe the new behavior?
Described here
shoelace-style/shoelace#1185

## PR Checklist
- [x] Test: run `npm run test` and ensure that all tests pass
- [x] Target main branch (or an appropriate release branch if
appropriate for a bug fix)
- [x] Ensure that your contribution follows [standard accessibility
guidelines](https://docs.microsoft.com/en-us/microsoft-edge/accessibility/design).
Use tools like https://webhint.io/ to validate your changes.

## Additional Information
Thanks to Cory from shoelace

Co-authored-by: Nikola Metulev <[email protected]>

apps/pwabuilder/src/script/components/windows-form.ts

@@ -128,6 +128,11 @@ export class WindowsForm extends AppPackageFormBase {
           color: #757575;
         }
 
+        #languageDrop sl-menu-item:focus-within::part(base) {
+          color: #ffffff;
+          background-color: #4F3FB6;
+        }
+
         #languageDrop sl-menu-item::part(base):hover{
           color: #ffffff;
           background-color: #4F3FB6;

components/manifest-editor/src/components/manifest-info-form.ts

@@ -166,6 +166,16 @@ export class ManifestInfoForm extends LitElement {
         width: 100%;
       }
 
+      sl-menu-item:focus-within::part(base) {
+        color: #ffffff;
+        background-color: #4F3FB6;
+      }
+
+      sl-menu-item::part(base):hover{
+        color: #ffffff;
+        background-color: #4F3FB6;
+      }
+
       .error-color-field{
         border: 1px solid #eb5757 !important;
       }

components/manifest-editor/src/components/manifest-platform-form.ts

@@ -141,6 +141,11 @@ export class ManifestPlatformForm extends LitElement {
       sl-menu {
          width: 100%;
       }
+      sl-menu-item:focus-within::part(base) {
+        color: #ffffff;
+        background-color: #4F3FB6;
+      }
+
       sl-menu-item::part(base):hover{
         color: #ffffff;
         background-color: #4F3FB6;

components/manifest-editor/src/components/manifest-settings-form.ts

@@ -202,6 +202,11 @@ export class ManifestSettingsForm extends LitElement {
         line-height: 16px;
         margin-left: .25em;
       }
+
+      sl-menu-item:focus-within::part(base) {
+        color: #ffffff;
+        background-color: #4F3FB6;
+      }
       
       sl-menu-item::part(base):hover {
         color: #ffffff;