chore: corrected currency update logic to prevent mixing major and minor update

[aryamohanan]

There are a couple of issues:

1. When a major update is applied, minor updates are also being included.
2. When multiple major updates occur, it additionally includes the major version updates from packages in the previously created PR, along with other minor updates.

see this PR #2461

[abhilash-sivan]

test results:

case 1: currency-bot branch exists
case2: currency-bot does not exists

Case 1:
The major version is being added to the version list, which I don’t think is necessary. If a breaking change requires supporting multiple major versions, we can handle that explicitly when needed.
Also, this change aggregates all major updates and is applied across all branches.
ie, test-3-ibmdb-400 an example branch which should only consist of ibm db changes does include both IBM DB, GOT, etc. (all major updates together)

Case 2:
Looks good — the major version is replaced instead. This aligns with what we likely need.
 
IMO we need case 2 result in the both scenarios

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[aryamohanan]

This condition was wrong earier

[aryamohanan]

We load the currencies file fresh, else it will load from the altered one.

[aryamohanan]

In both minor and major update we replace the latest current version in the version list.