Drop the -ubuntu-18.04.tar.xz builds

The workaround doesn't work for these builds, so maybe this is the time
to drop them. They're still in the CI because why not, may help make
testing whether the Wine bug has been fixed easier.

CHANGELOG.md

@@ -19,6 +19,10 @@ Versioning](https://semver.org/spec/v2.0.0.html).
   consider
   [downgrading](https://github.com/robbert-vdh/yabridge#downgrading-wine) back
   to Wine Staging 7.20.
+
+  **The `-ubuntu-18.04.tar.xz` builds are no longer provided from this release
+  onwards as they were still affected by the abovementioned bug.**
+
 - Yabridge's build system now errors out when doing unity builds with compiling
   with Wine 7.21 and 7.22.
 

README.md

@@ -104,10 +104,7 @@ Please let me know if there are any issues with other hosts.
      distro, you can simply download and install a prebuilt version of yabridge:
 
      1. First download the latest version of yabridge from the [releases
-        page](https://github.com/robbert-vdh/yabridge/releases). If you're using
-        a distro that's older than Ubuntu 20.04 such as Ubuntu 18.04, Debian 10,
-        Linux Mint 19, or AV Linux MXE 2021, then you should download the
-        version that ends with `-ubuntu-18.04.tar.gz`.
+        page](https://github.com/robbert-vdh/yabridge/releases).
      2. Extract the contents of the downloaded archive to `~/.local/share`, such
         that the file `~/.local/share/yabridge/yabridgectl` exists after
         extracting. You can extract an archive here from the command line with