Update linux dependency installation

Author: sarah-colq

.github/workflows/r_ci.yml

@@ -30,15 +30,15 @@ jobs:
         uses: r-lib/actions/setup-r@ffe45a39586f073cc2e9af79c4ba563b657dc6e3
         with:
           r-version: ${{ matrix.r-version }}
-      - name: Install libcurl
-        run: sudo apt-get install libcurl4-openssl-dev
+      - name: Install linux dependencies  
+        run: |
+            sudo apt-get install libcurl4-openssl-dev
+            sudo apt-get install libudunits2-dev
       - name: Cache R packages
         uses: actions/cache@v2
         with:
           path: ${{ env.R_LIBS_USER }}
           key: ${{ runner.os }}-r-1-
-      - name: Install linux dependencies  
-        run: sudo apt-get install libudunits2-dev
       - name: Install dependencies
         run: |
           install.packages(c("remotes", "rcmdcheck"))