Remove explicit installs of zoltr and covidData

Let's see what happens when we remove the build steps that install
zoltr and covidData (since these two packages are already listed
as dependencies in covidHubUtils)

.github/workflows/r_cmd_check.yaml

@@ -24,19 +24,6 @@ jobs:
           devtools::install_github("epiforecasts/[email protected]")
           devtools::install_deps(dependencies = TRUE)
         shell: Rscript {0}
-      - name: Install zoltr
-        run: |
-          devtools::install_github("reichlab/zoltr")
-          devtools::install()
-        shell: Rscript {0}
-      - name: Checkout covidData
-        uses: actions/checkout@v3
-        with:
-          repository: reichlab/covidData
-          path: covidData
-      - name: Install covidData
-        run: make recent_data
-        working-directory: ./covidData/code/data-processing
       - name: Check
         run: |
           devtools::check(args = c("--no-tests", "--no-manual", "--no-vignettes"),error_on = "error")