…ng multiple values

Fix role command that supports handling multiple values, CLI can create and delete multiple roles simultaneously.

…ng multiple values

Add test case.

…ng multiple values

Fix some issue due to reviewer's opinion.

…ng multiple values (apache#5988)

### What changes were proposed in this pull request?

In `GravitinoOptions`, the role option supports multiple values, but the
handleRoleCommand implementation currently only processes a single role
value. CLI should support create and delete multiple roles
simultaneously.


### Why are the changes needed?

Fix: apache#5985 

### Does this PR introduce _any_ user-facing change?

NO

### How was this patch tested?

local test + UT 

```bash
gcli role create -m demo_metalake --role role1 role2 role3
# role1, role2, role3 created

gcli role delete -m demo_metalake --role role1 role2 role3
# role1, role2, role3 deleted.

gcli role delete -m demo_metalake --role role1 role2 role3 unknown
# role1, role2, role3 deleted, but unknown is not deleted.

gcli role details -m demo_metalake
# Missing --role option.

gcli role details -m demo_metalake --role roleA roleB
# Exception in thread "main" java.lang.IllegalArgumentException: details requires only one role, but multiple are currently passed.
```