ci/github: Ubuntu 18.04 deprecated, add 23.04

https://github.blog/changelog/2022-08-09-github-actions-the-ubuntu-18-04-actions-runner-image-is-being-deprecated-and-will-be-removed-by-12-1-22/

.github/workflows/build.yml

@@ -8,18 +8,6 @@ on:
     branches:
       - '*'
 jobs:
-  ubuntu_22_04:
-    runs-on: ubuntu-22.04
-    steps:
-    - uses: actions/checkout@v2
-      with:
-        submodules: recursive
-    - name: Build ladi-jack2dbus
-      shell: bash
-      run: |
-        sudo apt-get install libdbus-1-dev
-        make
-
   ubuntu_20_04:
     runs-on: ubuntu-20.04
     steps:
@@ -32,8 +20,20 @@ jobs:
         sudo apt-get install libdbus-1-dev
         make
 
-  ubuntu_18_04:
-    runs-on: ubuntu-18.04
+  ubuntu_22_04:
+    runs-on: ubuntu-22.04
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        submodules: recursive
+    - name: Build ladi-jack2dbus
+      shell: bash
+      run: |
+        sudo apt-get install libdbus-1-dev
+        make
+
+  ubuntu_23_04:
+    runs-on: ubuntu-23.04
     steps:
     - uses: actions/checkout@v2
       with: