internal: Mark unresolved field, unresolved method and expected function diagnostics experimental

crates/ide-diagnostics/src/handlers/expected_function.rs

@@ -14,6 +14,7 @@ pub(crate) fn expected_function(
         format!("expected function, found {}", d.found.display(ctx.sema.db)),
         ctx.sema.diagnostics_display_range(d.call.clone().map(|it| it.into())).range,
     )
+    .experimental()
 }
 
 #[cfg(test)]

crates/ide-diagnostics/src/handlers/unresolved_field.rs

@@ -32,6 +32,7 @@ pub(crate) fn unresolved_field(
         ctx.sema.diagnostics_display_range(d.expr.clone().map(|it| it.into())).range,
     )
     .with_fixes(fixes(ctx, d))
+    .experimental()
 }
 
 fn fixes(ctx: &DiagnosticsContext<'_>, d: &hir::UnresolvedField) -> Option<Vec<Assist>> {

crates/ide-diagnostics/src/handlers/unresolved_method.rs

@@ -32,6 +32,7 @@ pub(crate) fn unresolved_method(
         ctx.sema.diagnostics_display_range(d.expr.clone().map(|it| it.into())).range,
     )
     .with_fixes(fixes(ctx, d))
+    .experimental()
 }
 
 fn fixes(ctx: &DiagnosticsContext<'_>, d: &hir::UnresolvedMethodCall) -> Option<Vec<Assist>> {