Change connected() to take &self instead of &mut self

[cuishuang]

The connected method only reads the connection status without mutating state, so &self is sufficient and avoids unnecessary mutable borrow.

[DanielEScherzer]

Looking at the various git_remote_connected callbacks in libgit2 there are none that mutate the remote, so looks good to me (once CI passes)

View changes since this review

[cuishuang]

Looking at the various git_remote_connected callbacks in libgit2 there are none that mutate the remote, so looks good to me (once CI passes)

View changes since this review

Thanks.

I resubmitted the changes and modified the test cases to pass the CI

[ehuss]

Is this safe even with a custom transport? The transport vtable does not seem to enforce this as const or have any comments or contracts around that.

[cuishuang]

Is this safe even with a custom transport? The transport vtable does not seem to enforce this as const or have any comments or contracts around that.

Oh, I missed the custom transport case. Even though git_remote_connected takes a const git_remote *, the transport vtable's is_connected callback takes a mutable git_transport *, and there does not seem to be a contract requiring it to be logically const.