Fix a typo in suitesparse.cc

Thanks Hyon Lim.

Change-Id: I73be87e805057427d5ad245beb30e1e177bae304
diff --git a/internal/ceres/suitesparse.cc b/internal/ceres/suitesparse.cc
index 57d12a1..9de32fd 100644
--- a/internal/ceres/suitesparse.cc
+++ b/internal/ceres/suitesparse.cc
@@ -334,7 +334,7 @@
              << "Ceres Solver was compiled with SuiteSparse "
              << "version 4.1.0 or less. Calling this function "
              << "in that case is a bug. Please contact the"
-             << "the Ceres Solver developers".
+             << "the Ceres Solver developers.";
 #endif
 }