add instantiation for docs

Author: sanjaylall

.github/workflows/documentation.yml

@@ -19,6 +19,11 @@ jobs:
           version: '1'
       - uses: ./.github/actions/juliatools
       - uses: ./.github/actions/juliamakedocsenv
+      - name: Install dependencies
+        shell: julia --color=yes --project=docs {0}
+        run: |
+          using Pkg
+          Pkg.instantiate()
       - name: Build and deploy
         run: julia --project=docs/ docs/make.jl