pypy3.5-c-jit-latest and pypy3.7-c-jit-latest are no longer available

* Fix erroneous use in tests that didn't show until now

The options is available since 3.10.0+ (https://github.com/python/cpython/pull/24820)
but has no effect until 3.11.0 (cpython b9e9292d75)
and broken in MacOS until 3.12.2 (cpython cc13eabc7c),
we add downstream patches to fix that except for 3.11-dev where we disabled it

3.15.0b1 released means we need 3.16 support

this checks if "no acceptable C compiler found" is in the last 10 lines of the log, and asks if the user has correctly installed the build dependencies.

Co-authored-by: Ivan Pozdeev <vano@mail.mipt.ru>

Introduced in 1.1.1-pre1

provides a reliable way for Pyenv code to locate other parts of Pyenv code that are not under `PYENV_ROOT`

* tests: Work with Git entirely in a test repo

Co-authored-by: Ivan Pozdeev <vano@mail.mipt.ru>

Citing https://www.postgrespro.ru/list/id/E1kfzRR-0001EH-Ph@gemulon.postgresql.org
fixing the same problem:
We previously put the -isysroot switch only into CPPFLAGS, theorizing
that it was only needed to find the right copies of include files.
However, it seems that we also need to use it while linking programs,
to find the right stub ".tbd" files for libraries.  We got away
without that up to now, but apparently that was mostly luck.  It may
also be that failures are only observed when the Xcode version is
noticeably out of sync with the host macOS version; the case that's
prompting action right now is that builds fail when using latest Xcode
(12.2) on macOS Catalina, even though it's fine on Big Sur.

Specifically, the problem arises for `preadv' and `pwritev' (new in MacOS 11 Big Sur) when building with XCode 12.4 (supporting Big Sur) in MacOS 10.15 Catalina.

Use tclConfig.sh/tkConfig.sh for future-proofing
3.14.0 doesn't detect Tcl/Tk with external libtommath, have to do it ourselves

Tcl/Tk 9.0 support was added in 3.13.0b3 and is not official as of 3.14.0;
the build with Homebrew version fails as of this writing

Fixes warnings "configure: WARNING: unrecognized options: --with-tcltk-libs, --with-tcltk-includes"

fix script

Apple CLang excludes it if -isysroot is passed

* Fix specifying XCode SDK for distutils

* Revert to preferring XCode Zlib

It turns out, everything since 2.7.12 and 3.5.2
can use libs from modern XCode SDK
which is always available unless we're using an alternate compiler

Zlib from XCode is virtually always present now so it only makes sense to use it from elsewhere if it's preferred.
Works around build failure for 2.7 that's incapable of using Zlib from XCode 7+ (see #3301)