I was using 3.0.14v Grails and I did some deployments to heroku. Everything was working fine, however I wanted to try with Grails 3.1.1 and I'm getting some errors now.
I was following this post https://devcenter.heroku.com/articles/deploying-gradle-apps-on-heroku
I cloned this https://github.com/kissaten/grails3-example
I think it's something about tomcat version but not sure.
Any help?
For your trouble with the compile 'com.github.jsimone:webapp-runner:8.0.30.1', I figured it out by removing the httpclient module from all test* import, and I imported a good version of that module (only for test*).
Thanks to that, I could import the "last" webapp-runner (directly as a jar)
Maybe that version of the webapp-runner will fix the problem, but I'm not sure. As I saw on your stacktraces, there is a NoClassDefFoundException for org/apache/tomcat/util/descriptor/tld/TldParser.
This class is provided by the tomcat-embed-core artifact. And that artifact comes from spring-boot-starter-tomcat (as a dependency). Change "spring-boot-starter-tomcat" from provided to compiled or try another version (for Grails 3.0.9, the spring-starter-tomcat version is 1.2.6).
Hope it helps ;)