Revert "CI: switching circleCI to use new engine and use proxy for ar… #326

Job	Run time
ubuntu-latest with Python 3.13	1m 27s
windows-latest with Python 3.13	2m 13s
ubuntu-latest with Python 3.14 and developer versioned dependencies	2m 43s
ubuntu-latest with Python 3.10 and oldest versioned dependencies	1m 29s
macos-latest with Python 3.13	1m 7s
ubuntu-latest with Python 3.11 and latest released version of dependencies	1m 17s
ubuntu-latest with Python 3.12 and latest or pre-release version of dependencies	1m 24s
	11m 40s

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