test: wrap mount/umount when running with sanitizers

On Fedora Rawhide mount/umount is linked against libsystemd, which then
breaks the binaries in sanitizer runs, as we try to run instrumented
code from an uninstrumented binary:

bash-5.3# ldd /usr/bin/mount
        linux-vdso.so.1 (0x00007fa757ef9000)
        libmount.so.1 => /lib64/libmount.so.1 (0x00007fa757e84000)
        libselinux.so.1 => /lib64/libselinux.so.1 (0x00007fa757e51000)
        libc.so.6 => /lib64/libc.so.6 (0x00007fa757c56000)
        libblkid.so.1 => /lib64/libblkid.so.1 (0x00007fa757c16000)
        libsystemd.so.0 => /lib64/libsystemd.so.0 (0x00007fa757400000)
        libpcre2-8.so.0 => /lib64/libpcre2-8.so.0 (0x00007fa75734f000)
        /lib64/ld-linux-x86-64.so.2 (0x00007fa757efb000)
        libclang_rt.asan.so => /usr/lib/clang/22/lib/x86_64-redhat-linux-gnu/libclang_rt.asan.so (0x00007fa756800000)
        libm.so.6 => /lib64/libm.so.6 (0x00007fa7566e4000)
        libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00007fa7566b7000)
        libstdc++.so.6 => /lib64/libstdc++.so.6 (0x00007fa756400000)
bash-5.3# mount
==458==ASan runtime does not come first in initial library list; you should either link runtime to your application or manually preload it with LD_PRELOAD.

This then breaks the whole machine, as mount is quite essential during
boot.

Let's just add mount/umount to the list of wrapped binaries to fix this.

mkosi/mkosi.sanitizers/mkosi.postinst

@@ -84,6 +84,7 @@ wrap=(
     mdadm
     mkfs.btrfs
     mksquashfs
+    mount
     multipath
     multipathd
     nvme
@@ -99,6 +100,7 @@ wrap=(
     su
     tar
     tgtd
+    umount
     unix_chkpwd
     useradd
     userdel