owncloud/core

Change: Update JavaScript dependencies

The following have been updated:
- ansi-regex (3.0.0 to 3.0.1)
- bower_components/backbone (1.4.0 to 1.4.1)
- bower_components/showdown (1.9.1 to 2.0.0)
- bower_components/underscore (1.13.1 to 1.13.2)
- follow-redirects (1.14.2 to 1.14.8)
- karma (6.3.8 to 6.3.19)
- karma-coverage (2.0.3 to 2.2.0)
- log4js (6.3.0 to 6.4.1)
- minimist (1.2.5 to 1.2.6)

https://github.com/owncloud/core/pull/39709
https://github.com/owncloud/core/pull/39763
https://github.com/owncloud/core/pull/39764
https://github.com/owncloud/core/pull/39785
https://github.com/owncloud/core/pull/39788
https://github.com/owncloud/core/pull/39814
https://github.com/owncloud/core/pull/39816
https://github.com/owncloud/core/pull/39838
https://github.com/owncloud/core/pull/39839
https://github.com/owncloud/core/pull/39926
https://github.com/owncloud/core/pull/39941
https://github.com/owncloud/core/pull/39989