Remove redundant jenkins_integration_tests.sh

CI jobs for Carrenza have been changed to use `jenkins_tests.sh` directly:

https://github.gds/gds/jenkins-config-ci-new/compare/d8cfee63e9b8caea85e4a0fd866168a4c45fc216...f2ee83a439628830a37d8b542d5333596f73875b

Excuse the other changes in that diff. It seems that Jenkins doesn't persist
changes with "apply" so they include other changes since the jobs were last
"saved".
Merge pull request #95 from gds-operations/72170126-remove_jenkins_integration_tests

[#72170126] Remove redundant jenkins_integration_tests.sh