chore/feat: few tweaks for "Check Potential Conflicts" action (#5330)

## Issue being fixed or feature implemented
small cleanups and improvements

## What was done?
pls see individual commits

## How Has This Been Tested?
see
https://github.com/dashpay/dash/actions/runs/4715728701/jobs/8362893373?pr=5330

## Breaking Changes
n/a

## Checklist:
- [x] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have added or updated relevant unit/integration/functional/e2e
tests
- [ ] I have made corresponding changes to the documentation
- [x] I have assigned this pull request to a milestone _(for repository
code-owners and collaborators only)_

.github/workflows/handle_potential_conflicts.py

@@ -1,23 +1,37 @@
-# Copyright (c) 2022 The Dash Core developers
+#!/usr/bin/env python3
+# Copyright (c) 2022-2023 The Dash Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+"""
+
+Usage:
+    $ ./handle_potential_conflicts.py <conflicts>
+
+Where <conflicts> is a json string which looks like
+    {   pull_number: 26,
+        conflictPrs:
+            [ { number: 15,
+                files: [ 'testfile1', `testfile2` ],
+                conflicts: [ 'testfile1' ] },
+                ...
+            ]}
+"""
+
 import sys
 import requests
 
 # need to install via pip
 import hjson
 
-'''Looks like'''
-'''{ pull_number: 26,
-    conflictPrs:
-        [ { number: 25,
-            files: [ '.github/workflows/testfile' ],
-            conflicts: [ '.github/workflows/testfile' ] }
-        { number: 24,
-            files: [ '.github/workflows/testfile' ],
-            conflicts: [ '.github/workflows/testfile' ] } ] }'''
+def get_label(pr_num):
+    return requests.get(f'https://api.github.com/repos/dashpay/dash/pulls/{pr_num}').json()['head']['label']
 
 def main():
+    if len(sys.argv) != 2:
+        print(f'Usage: {sys.argv[0]} <conflicts>', file=sys.stderr)
+        sys.exit(1)
+
     input = sys.argv[1]
     print(input)
     j_input = hjson.loads(input)
@@ -58,10 +72,5 @@ def main():
         sys.exit(1)
 
 
-
-def get_label(pr_num):
-    return requests.get(f'https://api.github.com/repos/dashpay/dash/pulls/{pr_num}').json()['head']['label']
-
-
 if __name__ == "__main__":
     main()

.github/workflows/predict-conflicts.yml

@@ -21,8 +21,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: check for potential conflicts
-        uses: PastaPastaPasta/potential-conflicts-checker-action@0.1.9
+        uses: PastaPastaPasta/potential-conflicts-checker-action@v0.1.10
         with:
           ghToken: "${{ secrets.GITHUB_TOKEN }}"
+      - name: Checkout
+        uses: actions/checkout@v2
       - name: validate potential conflicts
-        run: wget https://raw.githubusercontent.com/dashpay/dash/develop/.github/workflows/handle_potential_conflicts.py && pip3 install hjson && python3 handle_potential_conflicts.py "$conflicts"
+        run: pip3 install hjson && .github/workflows/handle_potential_conflicts.py "$conflicts"