debugger: More tidy up for SSH (#28993)

Split `locator` out of DebugTaskDefinition to make it clearer when
location needs to happen.

Release Notes:

- N/A

---------

Co-authored-by: Anthony Eid <hello@anthonyeid.me>
Co-authored-by: Anthony <anthony@zed.dev>
Co-authored-by: Cole Miller <m@cole-miller.net>

crates/workspace/Cargo.toml

@@ -35,7 +35,6 @@ client.workspace = true
 clock.workspace = true
 collections.workspace = true
 component.workspace = true
-dap.workspace = true
 db.workspace = true
 derive_more.workspace = true
 fs.workspace = true