test: repro for #10675 (#10676)

Signed-off-by: Etienne Millon <[email protected]>

test/blackbox-tests/test-cases/github10675.t

@@ -0,0 +1,25 @@
+When several executables have the same name and different sets of foreign
+stubs, dune should not crash. See #10675.
+
+  $ cat > dune << EOF
+  > (executable
+  >  (enabled_if false)
+  >  (name main))
+  >  
+  > (executable
+  >  (name main)
+  >  (foreign_stubs
+  >   (language c)
+  >   (names startup)))
+  > EOF
+
+  $ cat > dune-project << EOF
+  > (lang dune 3.0)
+  > EOF
+
+  $ touch startup.c main.ml
+
+  $ dune build 2>&1 | head -n 3
+  Internal error, please report upstream including the contents of _build/log.
+  Description:
+    ("Map.of_list_map_exn", { key = "main" })