fix(tests): Make allowBuilds in the js pnpm-workspace a mapping instead of list

[TartanLlama]

allowBuilds in test/components/js/pnpm-workspace.yaml is currently a list, but it is specified to be a mapping and the current version throws an error for me when running just build:

Error:   × load configuration
  ╰─▶ Failed to parse pnpm-workspace.yaml at jco/test/components/js/pnpm-workspace.yaml: error: line 3 column 14: unexpected event: expected mapping start
       --> <input>:3:14
        |
      1 | minimumReleaseAge: 10080
      2 | blockExoticSubdeps: true
      3 | allowBuilds: []
        |              ^ unexpected event: expected mapping start
      4 |
      5 | packages:
        |

We could probably also just remove it, whichever.