cli: implement the rad remote rm command

Implementing the `rad remote rm` command in order to be able
to remote a remote inside the radicle remote list.

Signed-off-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>

radicle-cli/src/commands/remote/rm.rs

@@ -0,0 +1,11 @@
+use crate::git;
+use crate::terminal as term;
+
+pub fn run(repository: &git::Repository, name: &str) -> anyhow::Result<()> {
+    if !git::is_remote(repository, name)? {
+        anyhow::bail!("remote `{name}` not found");
+    }
+    repository.remote_delete(name)?;
+    term::success!("Remote `{name}` removed");
+    Ok(())
+}