2023-01-03 main branch e2e-failures RHEL 9 AMD64

[dtrudg]

--- FAIL: TestE2E (639.58s)
    --- FAIL: TestE2E/SEQ (285.98s)
        --- FAIL: TestE2E/SEQ/CONFIG (25.73s)
            --- FAIL: TestE2E/SEQ/CONFIG/config_global (20.63s)
                --- FAIL: TestE2E/SEQ/CONFIG/config_global/AllowKernelExtfsNo_Container (0.09s)

[dtrudg]

FUSE mount did not occur:

=== RUN   TestE2E/SEQ/CONFIG/config_global/AllowKernelExtfsNo_Container
    singularitycmd.go:698: Running command "/usr/local/bin/singularity config global --set allow kernel extfs no"
    config.go:734: Running command "/usr/local/bin/singularity exec /tmp/config-12390254/ext3.img true"
    config.go:734: 
        "/usr/local/bin/singularity exec /tmp/config-12390254/ext3.img true" output:
        INFO:    Mounting image with FUSE.
        fuse: failed to exec fusermount: No such file or directory
        WARNING: passwd file doesn't exist in container, not updating
        WARNING: group file doesn't exist in container, not updating
        WARNING: Skipping mount /tmp [tmp]: /tmp doesn't exist in container
        WARNING: Skipping mount /var/tmp [tmp]: /var/tmp doesn't exist in container
        FATAL:   "true": executable file not found in $PATH
        /usr/bin/fusermount3: entry for /tmp/stest.1693995546/e2e-imgcache-2059714218/rootfs-78192472/root not found in /etc/mtab
        ERROR:   While running host cleanup tasks: while unmounting fuse directory: /tmp/stest.1693995546/e2e-imgcache-2059714218/rootfs-78192472/root: exit status 1
        ERROR:   Unprivileged host cleanup failed: host cleanup failed
        FATAL:   While reading from post start socket: EOF
        
    config.go:734: got 255 as exit code and was expecting 0: exit status 255
        waiting for command "/usr/local/bin/singularity exec /tmp/config-12390254/ext3.img true"
        github.com/sylabs/singularity/v4/e2e/internal/e2e.TestEnv.RunSingularity.func1
                github.com/sylabs/singularity/v4/e2e/internal/e2e/singularitycmd.go:673
        testing.tRunner
                testing/testing.go:1595
        runtime.goexit
                runtime/asm_amd64.s:1650

Is fusermount (FUSE v2) not present for fuse2fs in the test environment?