Merge JoinMarket-Org/joinmarket-clientserver#1470: CI: Bump used GitHub Actions to newer versions

224de08437 CI: Bump used GitHub Actions to newer versions (Kristaps Kaupe)

Pull request description:

  Updates [`actions/checkout`](https://github.com/actions/checkout), [`actions/setup-python`](https://github.com/actions/setup-python) and [`actions/cache`](https://github.com/actions/cache) to newest versions. Probably could help with random CI failures we are currently having.

ACKs for top commit:
  AdamISZ:
    ACK 224de08437

Tree-SHA512: b88850b7d2d50d1730d895dd195d8a7e139ec66d6cad7d055ee1495bd85692413f0934af6d697a618c8fee24993ad9b5aaeba6e6175a0639bf0418f4e63e32b9

.github/workflows/unittests.yml

@@ -12,14 +12,14 @@ jobs:
         python-version: ["3.7", "3.8", "3.9", "3.10", "3.11"]
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
       - name: Cache venv
         id: cache-venv
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         env:
           cache-name: venv
         with:
@@ -35,7 +35,7 @@ jobs:
       - name: Lint with flake8
         run: ./jmvenv/bin/flake8 -v jmclient jmbase jmbitcoin jmdaemon scripts
       - name: Cache bitcoind
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         env:
           cache-name: bitcoind
         with:
@@ -44,7 +44,7 @@ jobs:
       - name: Install bitcoind
         run: ./test/testrunner/install_bitcoind.sh
       - name: Cache miniircd
-        uses: actions/cache@v2
+        uses: actions/cache@v3
         env:
           cache-name: miniircd
         with: