The previous parser only considered stats files _starting_ with the
timestamp tag, not stats files having the timestamp tag in a later
position. While this applies to all current stats files, a future
stats file might look differently. Better to fix the function now than
be surprised in another 9 years from now.

This commit also adds a test case for such future stats, and it fixes
stats file paths in newly added unit tests.

It turns out that 9 years ago, we stopped appending data into stats file and
rather overwrite everytime we have new stats (see commit
a6a127c833eace1100aca7ab8ad118862bb8a8b9)

The load_stats_file() function was still thinking that we could have the same
line many times in the file which turns out to be false since 9 years ago.
However, that did not cause problem until IPv6 connection stats came along
which introduced a new line in conn-stats: "ipv6-conn-bi-direct ...".

Before, that file contained a single line starting with the tag
"conn-bi-direct".  That very tag appears also in the IPv6 tag (see above) so
the load_stats_file() function would consider that the IPv6 line as the last
tag to be appeneded to the file and fail to report the line above (for IPv4).
It would actually truncate the IPv6 line and report it (removing the "ipv6-"
part).

In other words, "conn-bi-direct" was not reported and instead
"ipv6-conn-bi-direct" was used without the "ipv6-" part.

This commit refactors the entire function so that now it looks for a
"timestamp tag" to validate and then if everything is fine, returns the entire
content of the file. The refactor simplifies the function, adds logging in
case of failures and modernize it in terms of coding standard.

Unit tests are also added that makes sure the loaded content matches the
entire file if timestamp validation passes.

Fixes #40226

Signed-off-by: David Goulet <dgoulet@torproject.org>

Adds a more user-friendly error message when the configuration is
reloaded and a new %include is added that makes its unglobbing
access files/folders not allowed by the seccomp sandbox.

Fixes #40205

Signed-off-by: David Goulet <dgoulet@torproject.org>

The "-static" compile flag was set globally which means that all autoconf test
were attempting to be built statically and lead to failures of detecting
OpenSSL libraries and others.

This commit adds this flag only to the "tor" binary build.

There is also a fix on where to find libevent.a since it is using libtool, it
is in .libs/.

At this commit, there are still warnings being emitted that informs the user
that the built binary must still be linked dynamically with glibc.

Fixes #40111

Signed-off-by: David Goulet <dgoulet@torproject.org>