Fix the unexpected RunningContext recreation in the Tomcat plugin. (#6001)

CHANGES.md

@@ -12,6 +12,7 @@ Release Notes.
 * The operation name of quartz-scheduler plugin, has been changed as the `quartz-scheduler/${className}` format.
 * Fix jdk-http and okhttp-3.x plugin did not overwrite the old trace header.
 * Support collecting logs of log4j, log4j2, and logback in the tracing context with a new `logger-plugin`.
+* Fix the unexpected RunningContext recreation in the Tomcat plugin.
 
 #### OAP-Backend
 * Make meter receiver support MAL.

apm-sniffer/apm-sdk-plugin/tomcat-7.x-8.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/tomcat78x/TomcatInvokeInterceptor.java

@@ -101,8 +101,8 @@ public class TomcatInvokeInterceptor implements InstanceMethodsAroundInterceptor
         if (!TomcatPluginConfig.Plugin.Tomcat.COLLECT_HTTP_PARAMS && span.isProfiling()) {
             collectHttpParam(request, span);
         }
-        ContextManager.stopSpan();
         ContextManager.getRuntimeContext().remove(Constants.FORWARD_REQUEST_FLAG);
+        ContextManager.stopSpan();
         return ret;
     }