test(fixtures): add private GitHub repository Plugin

apps/cli/tests/fixtures/github-repository-plugin/.dsh-plugin/package.json

@@ -0,0 +1,13 @@
+{
+  "name": "dsh-github-repository-plugin-e2e-fixture",
+  "version": "0.0.0",
+  "private": true,
+  "scripts": {
+    "prepare": "dsh-plugin-prepare"
+  },
+  "dsh": {
+    "skills": [
+      "../skills"
+    ]
+  }
+}

apps/cli/tests/fixtures/github-repository-plugin/skills/github-source-proof/SKILL.md

@@ -0,0 +1,6 @@
+---
+name: github-source-proof
+description: Proves that dsh installed a private repository Plugin from an exact GitHub source.
+---
+
+This skill exists only in the GitHub repository source fixture.