OCT-2027: Mobile navbar has bugs (#469)

## Description

## Definition of Done

1. [ ] If required, the desciption of your change is added to the [QA
changelog](https://www.notion.so/octantapp/Changelog-for-the-QA-d96fa3b411cf488bb1d8d9a598d88281)
2. [ ] Acceptance criteria are met.
3. [ ] PR is manually tested before the merge by developer(s).
    - [ ] Happy path is manually checked.
4. [ ] PR is manually tested by QA when their assistance is required
(1).
- [ ] Octant Areas & Test Cases are checked for impact and updated if
required (2).
5. [ ] Unit tests are added unless there is a reason to omit them.
6. [ ] Automated tests are added when required.
7. [ ] The code is merged.
8. [ ] Tech documentation is added / updated, reviewed and approved
(including mandatory approval by a code owner, should such exist for
changed files).
    - [ ] BE: Swagger documentation is updated.
9. [ ] When required by QA:
    - [ ] Deployed to the relevant environment.
    - [ ] Passed system tests.

---

(1) Developer(s) in coordination with QA decide whether it's required.
For small tickets introducing small changes QA assistance is most
probably not required.

(2) [Octant Areas & Test
Cases](https://docs.google.com/spreadsheets/d/1cRe6dxuKJV3a4ZskAwWEPvrFkQm6rEfyUCYwLTYw_Cc).

client/src/components/shared/Layout/Layout.tsx

@@ -61,7 +61,7 @@ const Layout: FC<LayoutProps> = ({
     const topBarWrapperEl = topBarWrapperRef.current;
 
     const listener = e => {
-      if (e.target.body.className === 'bodyFixed') {
+      if (e.target.body.className === 'bodyFixed' || window.scrollY < 0) {
         return;
       }
       const { offsetTop, clientHeight } = topBarWrapperEl;