Don't use shared bind mounts

Currently podman is invoked with options to mount both the workspace
directory and some of the files it contains. For example, if the
workspace is `/root`:

```
-v /root/.netrc:/root/.netrc:ro
-v /root:/root:rw,shared
```

The workspace directory is mounted using the _shared_ option. This
results in leaking mount points at an exponential rate, as descrived in
this _podman_ issue (no closed, as it is the expected behaviour):

  containers/podman#15671

This _shared_ option is not really needed. This patch removes it.

Signed-off-by: Juan Hernandez <juan.hernandez@redhat.com>

skipper/runner.py

@@ -138,7 +138,7 @@ def handle_volumes_bind_mount(docker_cmd, homedir, volumes, workspace):
 
     if utils.get_runtime_command() == utils.PODMAN:
         volumes.extend([
-            '%(workspace)s:%(workspace)s:rw,shared' % dict(workspace=workspace),
+            '%(workspace)s:%(workspace)s:rw' % dict(workspace=workspace),
             '%s:/opt/skipper/skipper-entrypoint.sh:rw' % utils.get_extra_file("skipper-entrypoint.sh"),
         ])
         if os.path.exists('/var/run/docker.sock'):

tests/test_runner_podman.py

@@ -86,7 +86,7 @@ def test_run_simple_command_nested_network_exist(self, resource_filename_mock, c
             '-v', get_volume_mapping('%(homedir)s/.gitconfig:%(homedir)s/.gitconfig:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('%(homedir)s/.docker/config.json:%(homedir)s/.docker/config.json:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('/etc/docker:/etc/docker:ro'),
-            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw,shared' % dict(workdir=WORKDIR)),
+            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw' % dict(workdir=WORKDIR)),
             '-v', get_volume_mapping('entrypoint.sh:/opt/skipper/skipper-entrypoint.sh:rw'),
             '-v', get_volume_mapping('/var/run/docker.sock:/var/run/docker.sock:rw'),
             '-v', get_volume_mapping('/var/lib/osmosis:/var/lib/osmosis:rw'),
@@ -127,7 +127,7 @@ def test_run_simple_command_nested_network_not_exist(self, resource_filename_moc
             '-v', get_volume_mapping('%(homedir)s/.gitconfig:%(homedir)s/.gitconfig:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('%(homedir)s/.docker/config.json:%(homedir)s/.docker/config.json:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('/etc/docker:/etc/docker:ro'),
-            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw,shared' % dict(workdir=WORKDIR)),
+            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw' % dict(workdir=WORKDIR)),
             '-v', get_volume_mapping('entrypoint.sh:/opt/skipper/skipper-entrypoint.sh:rw'),
             '-v', get_volume_mapping('/var/run/docker.sock:/var/run/docker.sock:rw'),
             '-v', get_volume_mapping('/var/lib/osmosis:/var/lib/osmosis:rw'),
@@ -168,7 +168,7 @@ def test_run_complex_command_nested(self, resource_filename_mock, check_output_m
             '-v', get_volume_mapping('%(homedir)s/.gitconfig:%(homedir)s/.gitconfig:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('%(homedir)s/.docker/config.json:%(homedir)s/.docker/config.json:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('/etc/docker:/etc/docker:ro'),
-            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw,shared' % dict(workdir=WORKDIR)),
+            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw' % dict(workdir=WORKDIR)),
             '-v', get_volume_mapping('entrypoint.sh:/opt/skipper/skipper-entrypoint.sh:rw'),
             '-v', get_volume_mapping('/var/run/docker.sock:/var/run/docker.sock:rw'),
             '-v', get_volume_mapping('/var/lib/osmosis:/var/lib/osmosis:rw'),
@@ -213,7 +213,7 @@ def test_run_non_existent_unauthorized_volume(self, resource_filename_mock,
             '-v', get_volume_mapping('%(homedir)s/.gitconfig:%(homedir)s/.gitconfig:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('%(homedir)s/.docker/config.json:%(homedir)s/.docker/config.json:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('/etc/docker:/etc/docker:ro'),
-            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw,shared' % dict(workdir=WORKDIR)),
+            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw' % dict(workdir=WORKDIR)),
             '-v', get_volume_mapping('entrypoint.sh:/opt/skipper/skipper-entrypoint.sh:rw'),
             '-v', get_volume_mapping('/var/run/docker.sock:/var/run/docker.sock:rw'),
             '-v', get_volume_mapping('/var/lib/osmosis:/var/lib/osmosis:rw'),
@@ -256,7 +256,7 @@ def test_run_complex_command_nested_with_env(self, resource_filename_mock, check
             '-v', get_volume_mapping('%(homedir)s/.gitconfig:%(homedir)s/.gitconfig:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('%(homedir)s/.docker/config.json:%(homedir)s/.docker/config.json:ro' % dict(homedir=HOME_DIR)),
             '-v', get_volume_mapping('/etc/docker:/etc/docker:ro'),
-            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw,shared' % dict(workdir=WORKDIR)),
+            '-v', get_volume_mapping('%(workdir)s:%(workdir)s:rw' % dict(workdir=WORKDIR)),
             '-v', get_volume_mapping('entrypoint.sh:/opt/skipper/skipper-entrypoint.sh:rw'),
             '-v', get_volume_mapping('/var/run/docker.sock:/var/run/docker.sock:rw'),
             '-v', get_volume_mapping('/var/lib/osmosis:/var/lib/osmosis:rw'),