Download toolchains using proxy if one is set in the environment #67

Job	Run time
Release Build Check	4m 53s
Format Check / Linux (6.0 - jammy)	1m 29s
Test / Linux (6.0 - jammy)	4m 46s
Test / Linux (6.0 - focal)	4m 53s
Test / Linux (6.0 - rhel-ubi9)	16m 31s
Test / Windows (${{ matrix.swift_version }} - ${{ ((contains(matrix.swift_version, 'nightly') && 'windows-2019') \|\| 'windows-2022') }})	0s
Test / Linux (6.0 - noble)	4m 41s
Test / Linux (6.0 - bookworm)	4m 50s
Test / Linux (6.0 - fedora39)	11m 42s
Format Check / Windows (${{ matrix.swift_version }} - ${{ ((contains(matrix.swift_version, 'nightly') && 'windows-2019') \|\| 'windows-2022') }})	0s
Soundness / Documentation check	0s
Soundness / Broken symlinks check	5s
Soundness / API breakage check	0s
Soundness / Format check	0s
Soundness / License headers check	0s
Soundness / Shell check	0s
Soundness / Unacceptable language check	5s
Soundness / Python lint check	6s
Soundness / YAML lint check	3s
	54m 4s

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