Fix variable assignment order in CompileTools.ts

[worksofliam]

Changes

Because BRANCH was before BRANCHLIB, I was getting the incorrect value in BRANCHLIB as &BRANCHLIB was evaluating to some/random/branchLIB

Checklist

• have tested my change

[worksofliam]

Test:

  {
    "name": "Test branch name",
    "command": "echo '&BRANCH &BRANCHLIB'",
    "environment": "pase",
    "extensions": [
      "GLOBAL"
    ]
  }

 *  Executing task: IBM i: Test branch name 

Commands:
                echo 'main VS24334339'

main VS24334339

[sebjulliand]

It took me a few minutes to understand why the order was important 😅