catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I93925bf34b4fec181a56d6524cbe9c6182a16b1f
diff --git a/http/routing.hpp b/http/routing.hpp
index d2a10b2..5d9c8e3 100644
--- a/http/routing.hpp
+++ b/http/routing.hpp
@@ -1204,7 +1204,7 @@
         {
             rules[ruleIndex]->handleUpgrade(req, res, std::move(adaptor));
         }
-        catch (std::exception& e)
+        catch (const std::exception& e)
         {
             BMCWEB_LOG_ERROR << "An uncaught exception occurred: " << e.what();
             res.result(boost::beast::http::status::internal_server_error);
diff --git a/src/crow_test.cpp b/src/crow_test.cpp
index a685220..0df05d2 100644
--- a/src/crow_test.cpp
+++ b/src/crow_test.cpp
@@ -58,7 +58,7 @@
         r.validate();
         fail("empty handler should fail to validate");
     }
-    catch (runtime_error& e)
+    catch (const runtime_error& e)
     {}
 
     int x = 0;
@@ -412,7 +412,7 @@
             c.receive(asio::buffer(buf, 2048));
             fail();
         }
-        catch (std::exception& e)
+        catch (const std::exception& e)
         {
             // std::cerr << e.what() << std::endl;
         }
@@ -891,7 +891,7 @@
         app.routeDynamic("/invalid_test/<double>/<path>")([]() { return ""; });
         fail();
     }
-    catch (std::exception&)
+    catch (const std::exception&)
     {}
 
     // app is in an invalid state when routeDynamic throws an exception.
@@ -900,7 +900,7 @@
         app.validate();
         fail();
     }
-    catch (std::exception&)
+    catch (const std::exception&)
     {}
 
     {