catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I6a2316d11f1dd70d8dc2368c2aa01d88cf1cdb26
diff --git a/libpldmresponder/bios_config.cpp b/libpldmresponder/bios_config.cpp
index 57e2dc9..e955f26 100644
--- a/libpldmresponder/bios_config.cpp
+++ b/libpldmresponder/bios_config.cpp
@@ -799,7 +799,7 @@
     {
         attrNameHdl = biosStringTable.findHandle(attrName);
     }
-    catch (std::invalid_argument& e)
+    catch (const std::invalid_argument& e)
     {
         std::cerr << "Could not find handle for BIOS string, ATTRIBUTE="
                   << attrName.c_str() << "\n";