catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ic2b49715c7b81ac5bcfc12ff2d3b4c593cd95ce7
diff --git a/user_channel/channel_mgmt.cpp b/user_channel/channel_mgmt.cpp
index a0fbcb7..41b477d 100644
--- a/user_channel/channel_mgmt.cpp
+++ b/user_channel/channel_mgmt.cpp
@@ -806,7 +806,7 @@
     {
         data = Json::parse(jsonFile, nullptr, false);
     }
-    catch (Json::parse_error& e)
+    catch (const Json::parse_error& e)
     {
         log<level::DEBUG>("Corrupted channel config.",
                           entry("MSG=%s", e.what()));