ci: Update pinned Nixpkgs

From the nixpkgs-unstable channel: https://hydra.nixos.org/eval/1815229#tabs-inputs

Changed files
+2 -2
ci
+2 -2
ci/pinned-nixpkgs.json
···
{
-
"rev": "573c650e8a14b2faa0041645ab18aed7e60f0c9a",
-
"sha256": "0qg99zj0gb0pc6sjlkmwhk1c1xz14qxmk6gamgfmcxpsfdp5vn72"
+
"rev": "eaeed9530c76ce5f1d2d8232e08bec5e26f18ec1",
+
"sha256": "132nimgi1g88fbhddk4b8b1qk68jly494x2mnphyk3xa1d2wy9q7"
}