Simplify the docs workflow

Installing and instantiating is handled by the make.jl script

.github/workflows/CI.yml

@@ -49,23 +49,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
+      - uses: julia-actions/cache@v1
       - uses: julia-actions/setup-julia@v1
-        with:
-          version: '1'
-      - run: |
-          julia --project=docs -e '
-            using Pkg
-            Pkg.develop([
-              PackageSpec(path=pwd()),
-              PackageSpec(path=joinpath(pwd(), "test", "Example.jl"))
-            ])
-            Pkg.instantiate()'
-      - run: |
-          julia --project=docs -e '
-            using Documenter: DocMeta, doctest
-            using PkgJogger
-            DocMeta.setdocmeta!(PkgJogger, :DocTestSetup, :(using PkgJogger); recursive=true)
-            doctest(PkgJogger)'
       - run: julia --project=docs docs/make.jl
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}