fix(bootstrap): Improving robustness and test coverage for bootstrap poetry command

[robdmoore]

Uses system python to invoke pipx rather than the current venv

@achidlow to throw a spanner in the works, I don't think this will consistently work afterall. Somehow my windows setup has a non symlinked python.exe in .venv and no python.exe/python3.exe in the sys.base_prefix :O. Let's look together on Thursday?

[github-actions]

Coverage Report

File	Stmts	Miss	Cover	Missing
src/algokit
__init__.py	15	7	53%	6–13, 17–24, 32–34
__main__.py	2	2	0%	1–3
src/algokit/cli
init.py	165	16	90%	56, 203–204, 235, 238–240, 251, 289, 326, 335–337, 340–345, 360
src/algokit/core
bootstrap.py	100	16	84%	74, 94, 149, 152, 158–172
click_extensions.py	47	20	57%	40–43, 50, 56, 67–68, 73–74, 79–80, 91, 104–114
conf.py	27	9	67%	10–17, 24, 26
log_handlers.py	68	9	87%	44–45, 50–51, 63, 112–116, 125
proc.py	44	1	98%	94
sandbox.py	106	7	93%	82, 147, 163, 178–180, 195
TOTAL	907	87	90%

Tests	Skipped	Failures	Errors	Time
102	0 💤	0 ❌	0 🔥	9.415s ⏱️