add test for i32, fix incorrect location

Author: jsirs

src/test/ui/issues/issue-31076.stderr

@@ -1,11 +1,19 @@
 error[E0369]: binary operation `+` cannot be applied to type `{integer}`
-  --> $DIR/typeck-issue-31076-correct-trait-impl.rs:13:13
+  --> $DIR/issue-31076.rs:13:13
    |
 LL |     let x = 5 + 6;
    |             ^^^^^
    |
    = note: an implementation of `std::ops::Add` might be missing for `{integer}`
 
-error: aborting due to previous error
+error[E0369]: binary operation `+` cannot be applied to type `i32`
+  --> $DIR/issue-31076.rs:15:13
+   |
+LL |     let y = 5i32 + 6i32;
+   |             ^^^^^^^^^^^
+   |
+   = note: an implementation of `std::ops::Add` might be missing for `i32`
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0369`.