OCT-1962: Transactions component shows the same transaction twice (#418)

## 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/Home/HomeGridTransactions/TransactionsList/TransactionsList.tsx

@@ -17,9 +17,8 @@ const TransactionsList: FC<TransactionsListProps> = ({ history }) => {
 
   return (
     <Fragment>
-      {history.map((element, index) => (
-        // eslint-disable-next-line react/no-array-index-key
-        <TransactionsListItem key={index} {...element} />
+      {history.map(element => (
+        <TransactionsListItem key={`${element.type}_${element.timestamp}`} {...element} />
       ))}
     </Fragment>
   );