Rename consuming chaining methods on DiagnosticBuilder.

In #119606 I added them and used a `_mv` suffix, but that wasn't great.

A `with_` prefix has three different existing uses.
- Constructors, e.g. `Vec::with_capacity`.
- Wrappers that provide an environment to execute some code, e.g.
  `with_session_globals`.
- Consuming chaining methods, e.g. `Span::with_{lo,hi,ctxt}`.

The third case is exactly what we want, so this commit changes
`DiagnosticBuilder::foo_mv` to `DiagnosticBuilder::with_foo`.

Thanks to @compiler-errors for the suggestion.

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -2225,11 +2225,11 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         );
 
         self.thread_local_value_does_not_live_long_enough(borrow_span)
-            .span_label_mv(
+            .with_span_label(
                 borrow_span,
                 "thread-local variables cannot be borrowed beyond the end of the function",
             )
-            .span_label_mv(drop_span, "end of enclosing function is here")
+            .with_span_label(drop_span, "end of enclosing function is here")
     }
 
     #[instrument(level = "debug", skip(self))]