Remove custom curl build on community job

This should no longer be necessary now that we're on Ubuntu 20.04.

azure/community_job.yml

@@ -21,16 +21,6 @@ jobs:
       ubsan_options: 'print_stacktrace=1'
     steps:
     - template: apt.yml
-    - script: |
-        # Compile a newer version of curl, otherwise there will be an asan warning
-        # when running symfony tests.
-        wget https://curl.haxx.se/download/curl-7.65.3.tar.gz
-        tar xzf curl-7.65.3.tar.gz
-        cd curl-7.65.3/
-        ./configure
-        make -j2
-        sudo make install
-      displayName: 'Build Curl'
     - template: configure.yml
       parameters:
         configurationParameters: ${{ parameters.configurationParameters }}