Merge branch 'jk/leakfix'

Code clean-up.

* jk/leakfix:
  submodule--helper: fix leak of core.worktree value
  config: fix leak in git_config_get_expiry_in_days()
  config: drop git_config_get_string_const()
  config: fix leaks from git_config_get_string_const()
  checkout: fix leak of non-existent branch names
  submodule--helper: use strbuf_release() to free strbufs
  clear_pattern_list(): clear embedded hashmaps

diff --cc apply.c
Simple merge

diff --cc builtin/checkout.c
Simple merge

diff --cc builtin/fetch.c
Simple merge

diff --cc builtin/submodule--helper.c
Simple merge

diff --cc cache.h
Simple merge

diff --cc config.c
Simple merge

diff --cc connect.c
Simple merge

diff --cc dir.c
Simple merge

diff --cc environment.c
Simple merge

diff --cc help.c
Simple merge

diff --cc submodule.c
Simple merge