catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: If18cc0293b52ce5f7f8e068688aa17d28ed27d50
diff --git a/sol/sol_manager.cpp b/sol/sol_manager.cpp
index 2102032..698159d 100644
--- a/sol/sol_manager.cpp
+++ b/sol/sol_manager.cpp
@@ -261,7 +261,7 @@
                 });
         }
     }
-    catch (sdbusplus::exception_t& e)
+    catch (const sdbusplus::exception_t& e)
     {
         log<level::ERR>(
             "Failed to get service path in registerSOLServiceChangeCallback");