Merge JoinMarket-Org/joinmarket-clientserver#1738: CI: Bump Bitcoin Core to v28.0

d9da8bd38e CI: Bump Bitcoin Core to v28.0 (Kristaps Kaupe)

Pull request description:

  .

Top commit has no ACKs.

Tree-SHA512: 4343a1cf93143d860515c3111514cfca62d280675f5c2ccc76aeb0e419d25b09f090697703e41f3267ec87d6cfb012bc93970da89f6923a03b37748971d93868

.github/workflows/unittests.yml

@@ -10,7 +10,7 @@ jobs:
       matrix:
         os: [macos-13, ubuntu-latest]
         python-version: ["3.8", "3.12"]
-        bitcoind-version: ["24.0.1", "27.1"]
+        bitcoind-version: ["24.0.1", "28.0"]
 
     steps:
       - uses: actions/checkout@v3