TestDirectMount, TestForceOwner fail: fusermount requires user_allow_other in fuse.conf

[sapphirecat]

Running the tests generates a couple of errors, that seem to be the result of:

/usr/bin/fusermount3: option allow_other only allowed if 'user_allow_other' is set in /etc/fuse.conf

Setting the option as indicated causes all tests to pass which are run in that configuration.

System: Core i7-1260P, Pop!_OS 22.04, go1.21.1, libssl3-3.0.2-0ubuntu1.10 (the build was fine, but I needed the libssl-dev package installed to run ./test-without-openssl.bash.) gocryptfs commit 4ef110f (livin' on the edge! 😉)

In context:

ok  	github.com/rfjakob/gocryptfs/v2/internal/tlog	0.004s
?   	github.com/rfjakob/gocryptfs/v2/tests/symlink_race	[no test files]
?   	github.com/rfjakob/gocryptfs/v2/tests/test_helpers	[no test files]
UnmountErr: "/var/tmp/gocryptfs-test-parent-999/2004589698/TestMountBackground.2429970518.mnt" was not found in MountInfo, cannot check for FD leaks
UnmountErr: "/var/tmp/gocryptfs-test-parent-999/2004589698/TestConfigPipe.3527671620.mnt" was not found in MountInfo, cannot check for FD leaks
OpenDir ".": invalid entry "L0OZ7QcrnskygeNf4l15LgwrongPattern": bad message
Invalid cipherdir: directory /var/tmp/gocryptfs-test-parent-999/2004589698/TestInitNotEmpty not empty
/usr/bin/fusermount3: option allow_other only allowed if 'user_allow_other' is set in /etc/fuse.conf
fs.Mount failed: fusermount exited with code 256
--- FAIL: TestDirectMount (0.03s)
    directmount_test.go:52: mount failed: exit status 19
FAIL
FAIL	github.com/rfjakob/gocryptfs/v2/tests/cli	3.377s
ok  	github.com/rfjakob/gocryptfs/v2/tests/cluster	0.005s
/usr/bin/fusermount3: option allow_other only allowed if 'user_allow_other' is set in /etc/fuse.conf
fs.Mount failed: fusermount exited with code 256
--- FAIL: TestForceOwner (0.02s)
    main_test.go:441: mount failed: exit status 19
FAIL
FAIL	github.com/rfjakob/gocryptfs/v2/tests/defaults	1.068s
ok  	github.com/rfjakob/gocryptfs/v2/tests/deterministic_names	0.053s
ok  	github.com/rfjakob/gocryptfs/v2/tests/example_filesystems	0.799s
ok  	github.com/rfjakob/gocryptfs/v2/tests/fsck	0.417s