[PLAY-1724] Dark Mode - Map Audit (#4154)

**What does this PR do?** A clear and concise description with your
runway ticket url.
[PLAY-1724](https://runway.powerhrg.com/backlog_items/PLAY-1724)

This PR is a part of the Dark Mode Audit on 'Map'.
We've updated the pop up content, it should display a dark background
and white text.
Light mode was also impacted to create this change, the functionality
remains the same.

**Screenshots:** Screenshots to visualize your addition/change
<img width="1708" alt="403572936-e4954b35-59f1-43cb-814d-117a952b1a0b"
src="https://github.com/user-attachments/assets/3dc39783-ce46-421c-814c-c8084ea3376c"
/>

**How to test?** Steps to confirm the desired behavior:
1.  Go to playbook.powerapp.cloud/kits/map/react
2.  Enable 'dark mode'
3.  Check each map
4. Click on the location icon on the map --> all pop up content should
have a dark background and white text
5. Enable 'light mode', make sure the pop up content behaves the same
way as production

#### Checklist:
- [x] **LABELS** Add a label: `enhancement`, `bug`, `improvement`, `new
kit`, `deprecated`, or `breaking`. See [Changelog &
Labels](https://github.com/powerhome/playbook/wiki/Changelog-&-Labels)
for details.
- [ ] **DEPLOY** I have added the `milano` label to show I'm ready for a
review.
- [ ] **TESTS** I have added test coverage to my code.

Author: gabbymassaro

playbook-website/app/javascript/site_styles/map_styles/_map_default.scss

@@ -7,4 +7,13 @@
 .pb_map {
   height: 600px;
   position: relative;
+  [class^="pb_title_kit"][class*="_4"] {
+    color: $text_lt_default
+  }
+
+  .dark & {
+    [class^="pb_title_kit"][class*="_4"] {
+      color: $text_dk_default;
+    }
+  }
 }