Spack unable to parse miniconda3 URLs out of the box

[fdeponte]

Steps to reproduce

[rmladmin@ai-rmlsbatch1 ~]$ spack versions miniconda3 ==> Safe versions (already checksummed): 4.8.2 4.7.12.1 4.6.14 4.5.11 4.5.4 4.3.30 4.3.14 4.3.11 ==> Remote versions (not yet checksummed): ==> Error: Couldn't detect version in: https://repo.anaconda.com/miniconda/Miniconda3-py38_4.8.2-Linux-x86_64.sh

Error message

==> Safe versions (already checksummed): 4.8.2 4.7.12.1 4.6.14 4.5.11 4.5.4 4.3.30 4.3.14 4.3.11 ==> Remote versions (not yet checksummed): ==> Error: Couldn't detect version in: https://repo.anaconda.com/miniconda/Miniconda3-py38_4.8.2-Linux-x86_64.sh

Information on your system

[rmladmin@ai-rmlsbatch1 ~]$ spack debug report

• Spack: 0.16.0
• Python: 3.6.8
• Platform: linux-centos7-haswell

General information

• [X] I have run spack debug report and reported the version of Spack/Python/Platform
• [X] I have searched the issues of this repo and believe this is not a duplicate
• [X] I have run the failing commands in debug mode and reported the output

[alalazo]

Still happening with:

• Spack: 0.20.0.dev0 (4ace1e660a3ab60a2e510308d700e251126f8c0e)
• Python: 3.8.10
• Platform: linux-ubuntu20.04-icelake
• Concretizer: clingo