.gitmodules in congruence_solver-0.3.0 vs .gitmodules in congruence_solver-0.3.1

@@ -1,3 +1,4 @@
 [submodule "ext/congruence_solver"]
-	path = ext/congruence_solver
-	url = https://github.com/laneb/congruence_solver_ext.git
+  path = ext/congruence_solver
+  url = https://github.com/laneb/congruence_solver_ext.git
+  branch = master
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