fix(ci): actions/checkout with filter: "tree:0"

[wdconinc]

Briefly, what does this PR introduce?

This PR will make CI runs start just a few microseconds faster... :-\ This made more sense when we were doing checkouts of an entire 50k-commit spack tree with fulll history because we couldn't specify tree-less or blob-less...

What kind of change does this PR introduce?

• [x] Bug fix (issue #1371)
• [ ] New feature (issue #__)
• [ ] Documentation update
• [ ] Other: __

Please check if this PR fulfills the following:

• [ ] Tests for the changes have been added
• [ ] Documentation has been added / updated
• [ ] Changes have been communicated to collaborators

Does this PR introduce breaking changes? What changes might users need to make to their code?

No.

Does this PR change default behavior?

No.

[github-actions[bot]]

Capybara summary for PR 1374

• rec_dis_10x100_minQ2=1000_craterlake
• rec_dis_10x100_minQ2=1_craterlake
• rec_dis_18x275_minQ2=1000_craterlake
• rec_dis_18x275_minQ2=1_craterlake
• rec_dis_5x41_minQ2=1_craterlake
• rec_e_1GeV_20GeV_craterlake
• rec_pi_1GeV_20GeV_craterlake ^{_{Last updated 2024-04-09T03:34+00:00 69d2158159182fec1288cda1679f8f74f6a98445}}