Recommended update for salt

This update for salt fixes the following issues:

- Fix syntax error on pkgrepo state with Python 2.7
- transactional_update: unify with chroot.call
- Add `migrated` state and GPG key management functions
- Master can read grains
- Fix for broken psutil (bsc#1102248)
- Fix `novendorchange` handling in zypperpkg module

This update was imported from the SUSE:SLE-15-SP2:Update update project.

Fixed bugs
bnc#1102248
Salt ps.top module is broken on Python 3
Selected Binaries
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