tests: remove pkgsUnstable

The latest nixpkgs-unstable update would require node-based packages to
distinguish between stable and unstable when building. Instead of dealing with
that complexity, we will only guarantee compatability of our packages with
stable.

.cirrus.yml

@@ -15,8 +15,7 @@ task:
   # Use the maximum timeout. Needed when rebuilding packages on a channel update.
   timeout_in: 120m
 
-  matrix:
-    - name: modules_test
+  name: modules_test
   environment:
     nixpkgs: nixpkgs
   container:
@@ -31,10 +30,6 @@ task:
     - environment:
         scenario: netnsRegtest
 
-    - name: pkgs_unstable
-      environment:
-        nixpkgs: nixpkgs-unstable
-
   # This script is run as root
   build_script:
     - echo "sandbox = true" >> /etc/nix/nix.conf

test/pkgs-unstable.nix

@@ -1,12 +0,0 @@
-let
-  pinned = import ../pkgs/nixpkgs-pinned.nix;
-  pkgs = import pinned.nixpkgs-unstable {};
-  nbPkgs = import ../pkgs { inherit pkgs; };
-  pkgsUnstable = with nbPkgs; [
-    # Disabled because joinmarket dependencies currently don't build on on unstable.
-    # joinmarket
-    rtl
-    cl-rest
-  ];
-in
-pkgs.writeText "pkgs-unstable" (pkgs.lib.concatMapStringsSep "\n" toString pkgsUnstable)

test/run-tests.sh

@@ -246,10 +246,6 @@ vmTestNixExpr() {
 EOF
 }
 
-pkgsUnstable() {
-    doBuild pkgs-unstable "$scriptDir/pkgs-unstable.nix"
-}
-
 # A basic subset of tests to keep the total runtime within
 # manageable bounds (<4 min on desktop systems).
 # These are also run on the CI server.
@@ -257,7 +253,6 @@ basic() {
     scenario=default buildTest "$@"
     scenario=netns buildTest "$@"
     scenario=netnsRegtest buildTest "$@"
-    pkgsUnstable
 }
 
 # All tests that only consist of building a nix derivation.