build(deps): bump sigstore from 3.6.3 to 4.0.0 (#220)

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements/dev.in

@@ -5,5 +5,5 @@ mypy
 types-requests
 
 # copied from main.in
-sigstore ~= 3.6
+sigstore ~= 4.0
 requests ~= 2.32