show template values of exts_default_options in PythonBundle

[Flamefire]

(created using eb --new-pr)

When exts_default_options is logged the templating is already re-enabled. This means any template in that log entry will be resolved using the parent EC values not the ones that will actually be used by extensions.

Fix this by moving the print inside the disable-template section and use the context manager while at it.

[smoors]

tested with random pythonbundle easyconfig (wandb), fixes the issue.

relevant log line including exts_default_options:
original

== 2023-02-28 21:21:10,855 pythonbundle.py:79 INFO exts_default_options: {'buildcmd': None, 'check_ldshared': None, 'download_dep_fail': True, 'install_src': None, 'install_tar
get': 'install', 'pip_ignore_installed': True, 'pip_no_index': None, 'req_py_majver': None, 'req_py_minver': None, 'sanity_pip_check': True, 'runtest': True, 'testinstall': Fal
se, 'unpack_sources': None, 'unversioned_packages': [], 'use_pip': True, 'use_pip_editable': False, 'use_pip_extras': None, 'use_pip_for_deps': False, 'use_pip_requirement': Fa
lse, 'zipped_egg': False, 'source_urls': ['https://pypi.python.org/packages/source/w/wandb'], 'options': {}}

with this PR:

== 2023-03-03 22:59:38,840 pythonbundle.py:75 INFO exts_default_options: {'buildcmd': None, 'check_ldshared': None, 'download_dep_fail': True, 'install_src': None, 'install_tar
get': 'install', 'pip_ignore_installed': True, 'pip_no_index': None, 'req_py_majver': None, 'req_py_minver': None, 'sanity_pip_check': True, 'runtest': True, 'testinstall': Fal
se, 'unpack_sources': None, 'unversioned_packages': [], 'use_pip': True, 'use_pip_editable': False, 'use_pip_extras': None, 'use_pip_for_deps': False, 'use_pip_requirement': Fa
lse, 'zipped_egg': False, 'source_urls': ['https://pypi.python.org/packages/source/%(nameletter)s/%(name)s'], 'options': {}}

[smoors]

lgtm

[smoors]

Going in, thanks @Flamefire!