Deprecate `httpx` in favor of `httpx2` #2278

Job	Run time
checks / readme-snippets	15s
checks / pre-commit	32s
checks / test (3.11, lowest-direct, windows-latest)	3m 9s
checks / test (3.10, locked, ubuntu-latest)	1m 0s
checks / test (3.11, lowest-direct, ubuntu-latest)	59s
checks / test (3.10, locked, windows-latest)	2m 30s
checks / test (3.14, lowest-direct, ubuntu-latest)	1m 26s
checks / test (3.13, lowest-direct, ubuntu-latest)	55s
checks / test (3.14, locked, windows-latest)	4m 25s
checks / test (3.10, lowest-direct, windows-latest)	1m 43s
checks / test (3.12, lowest-direct, windows-latest)	3m 38s
checks / test (3.12, lowest-direct, ubuntu-latest)	1m 0s
checks / test (3.12, locked, ubuntu-latest)	57s
checks / test (3.11, locked, ubuntu-latest)	47s
checks / test (3.14, locked, ubuntu-latest)	2m 27s
checks / test (3.13, lowest-direct, windows-latest)	2m 37s
checks / test (3.11, locked, windows-latest)	2m 27s
checks / test (3.13, locked, windows-latest)	3m 12s
checks / test (3.12, locked, windows-latest)	3m 22s
checks / test (3.14, lowest-direct, windows-latest)	2m 44s
checks / test (3.10, lowest-direct, ubuntu-latest)	58s
checks / test (3.13, locked, ubuntu-latest)	46s
all-green	3s
	41m 52s

Provide feedback