mkosi: Drop two unnecessary settings in CI config

We don't build erofs images anymore and the firmware to use is set
per test so no need to configure it the CI config.

.github/workflows/mkosi.yml

@@ -111,8 +111,6 @@ jobs:
 
         [Content]
         Environment=
-                # mkfs.erofs is extremely noisy when not connected to a tty.
-                SYSTEMD_REPART_MKFS_OPTIONS_EROFS="--quiet"
                 # Build debuginfo packages since we'll be publishing the packages as artifacts.
                 WITH_DEBUG=1
                 # Enabling optimizations significantly speeds up integration tests.
@@ -121,8 +119,6 @@ jobs:
         [Host]
         ToolsTree=default
         ToolsTreeDistribution=fedora
-        # TODO: Drop once https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2038777 is fixed in Github Actions
-        QemuFirmware=uefi
         # We build with debuginfo so there's no point in mounting the sources into the machine.
         RuntimeBuildSources=no
         EOF