catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I2afb405177268451e44f0aff8417777a00d292d9
diff --git a/chassis_state_manager.cpp b/chassis_state_manager.cpp
index 5a3bd1a..fd2ef22 100644
--- a/chassis_state_manager.cpp
+++ b/chassis_state_manager.cpp
@@ -331,7 +331,7 @@
         }
         return false;
     }
-    catch (cereal::Exception& e)
+    catch (const cereal::Exception& e)
     {
         error("deserialize exception: {ERROR}", "ERROR", e);
         fs::remove(path);
@@ -388,7 +388,7 @@
             return true;
         }
     }
-    catch (std::exception& e)
+    catch (const std::exception& e)
     {
         error("deserialize exception: {ERROR}", "ERROR", e);
         fs::remove(path);