This includes removing (hopefully temporarily) the gradle-lint plugin as
it is incompatible with various Gradle versions (see
https://github.com/nebula-plugins/gradle-lint-plugin/issues/393). This
is somewhat unfortunate since the plugin is useful for removing unused
dependencies, though with the relatively small amount of Gradle code we
write hopefully it will not be missed much. If Nebula changes their
code to be compatible with Gradle 8+, we can re-add it easily.
This upgrade means we can remove the code added in 342051e1.
* Convert to gradle 7.
* More fixes, regenerated lockfiles.
* Update lockfiles for dependency update.
* Fix show_upgrade_diff for new lockfile format
* Add property for allowInsecureProtocol
Allow us to override the restriction against use of plain HTTP for
communication to dependency repositories. We need this to be able to use a
local proxy for dependency gathering.
* Checking in missing gradle.lockfile
