Update locs in tests given new Executables Dep_entry

Signed-off-by: Rudi Grinberg <[email protected]>

test/blackbox-tests/test-cases/lib-errors/run.t

@@ -10,7 +10,7 @@ Cycle detection
   -> "c" in _build/default
   -> "a" in _build/default
   -> required by library "c" in _build/default
-  -> required by executable cycle in dune:16
+  -> required by executable cycle in dune:17
   [1]
 
 Select with no solution
@@ -21,6 +21,6 @@ Select with no solution
   25 |  (libraries (select x from))
                    ^^^^^^^^^^^^^^^
   Error: No solution found for this select form.
-  -> required by executable select_error in dune:23
+  -> required by executable select_error in dune:24
   [1]
 

test/blackbox-tests/test-cases/variants/run.t

@@ -148,7 +148,7 @@ Executable that tries to build against a virtual library without an implementati
   $ dune build --root missing-implementation
   Entering directory 'missing-implementation'
   Error: No implementation found for virtual library "vlib" (_build/default/vlib).
-  -> required by executable foo in dune:1
+  -> required by executable foo in dune:2
   [1]
 
 Executable that tries to use two implementations for the same virtual lib
@@ -158,7 +158,7 @@ Executable that tries to use two implementations for the same virtual lib
   - "impl1" in _build/default/impl1
      -> required by library "bar" in _build/default
   - "impl2" in _build/default/impl2
-  This cannot work.-> required by executable foo in dune:1
+  This cannot work.-> required by executable foo in dune:2
   [1]
 
 Install files for implemenations and virtual libs have all the artifacts: