Support TLS tracing for Python applications linking `libpython`

[ddelnano]

While enhancing our TLS tracing to support Python 3.10 and later (#1113), I noticed there is an another type of Python application that Pixie cannot trace today -- python interpreters that link libpython.

This was uncovered when developing the python 3.10 openssl_trace_bpf_test test added in #1338. When using an alpine based python 3.10 docker image, the tests succeeds (as long as the _ex variants have probes attached). However when switching to the rules_docker python base image (built on distroless), the test would fail. This is due to distroless using a python interpreter with --enable-shared which results in libpython${VERSION} containing the OpenSSL symbols as seen below:

# Distroless python links libpython3.10.so.1.0 which contains the openssl symbols. See the second, very long line below
$ sudo ldd /proc/2081563/root/app/src/stirling/source_connectors/socket_tracer/testing/containers/ssl/python_min_310_https_server.binary.runfiles/python3_10_x86_64-unknown-linux-gnu/bin/python3
linux-vdso.so.1 (0x00007fffbdf98000)
/proc/2081563/root/app/src/stirling/source_connectors/socket_tracer/testing/containers/ssl/python_min_310_https_server.binary.runfiles/python3_10_x86_64-unknown-linux-gnu/bin/../lib/libpython3.10.so.1.0 (0x00007f1ae0b34000)
libcrypt.so.1 => /lib/x86_64-linux-gnu/libcrypt.so.1 (0x00007f1ae0ae7000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f1ae0ae2000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f1ae0add000)
libutil.so.1 => /lib/x86_64-linux-gnu/libutil.so.1 (0x00007f1ae0ad6000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f1ae09ef000)
librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f1ae09ea000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f1ae0600000)
/lib64/ld-linux-x86-64.so.2 (0x00007f1ae2001000)
 
$ sudo objdump -Tt /proc/2081563/root/app/src/stirling/source_connectors/socket_tracer/testing/containers/ssl/python_min_310_https_server.binary.runfiles/python3_10_x86_64-unknown-linux-gnu/lib/libpython3.10.so.1.0 \| grep SSL_write
0000000000b670e0 g     F .text  00000000000001c5              SSL_write_early_data
0000000000b67090 g     F .text  0000000000000040              SSL_write
0000000000b670d0 g     F .text  000000000000000f              SSL_write_ex
0000000000b670e0 g    DF .text  00000000000001c5  Base        SSL_write_early_data
0000000000b670d0 g    DF .text  000000000000000f  Base        SSL_write_ex
0000000000b67090 g    DF .text  0000000000000040  Base        SSL_write
 
# Inspecting a python interpreter that can be successfully TLS traced
$ ldd /usr/bin/python3.10
linux-vdso.so.1 (0x00007ffcedfdc000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f48c0719000)
libexpat.so.1 => /lib/x86_64-linux-gnu/libexpat.so.1 (0x00007f48c0e8a000)
libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f48c0e6e000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f48c0400000)
/lib64/ld-linux-x86-64.so.2 (0x00007f48c0ed0000)