Limit parallelism in CI

The jobs seem to be getting killed. Possibly too
much mem usage. Limit to 2 at once to squeeze by.

Author: john-shaffer

.github/workflows/build.yml

@@ -33,8 +33,8 @@ jobs:
 
       - name: Build all checks and outputs
         run: |
-          bin/test-releases
-          bin/test-php-versions
+          bin/test-releases 2
+          bin/test-php-versions 2
           nix develop ./dev -c om ci
           cd dev
           nix develop -c om ci

bin/test-php-versions

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
-parallel -j "$(nproc)" --tagstring "{1}" --line-buffer '
+parallel -j "${1:-$(nproc)}" --tagstring "{1}" --line-buffer '
   echo "Testing {1}"
   PHP_PACKAGE="{1}" nix flake check --impure ./dev
 ' ::: php84 php83 php82 php81

bin/test-releases

@@ -2,7 +2,7 @@
 set -euo pipefail
 
 # Test releases against the oldest and newest supported PHP versions
-parallel -j "$(nproc)" --tagstring "{1} {2}" --line-buffer '
+parallel -j "${1:-$(nproc)}" --tagstring "{1} {2}" --line-buffer '
   echo "Testing {2} with {1}"
   PHP_PACKAGE="{1}" STATIC_DEPLOY_PACKAGE="{2}" nix flake check --impure ./dev
 ' ::: php84 php81 ::: plugin pluginWpOrg