update GitHub workflow

Author: duncanpo

.github/workflows/build.yml

@@ -6,9 +6,7 @@ jobs:
     build-and-run-tests:
         runs-on: ubuntu-latest
         env:
-            OPENTELEMETRY_CPP_INSTALL: "${{ github.workspace }}/otel_cpp_install"
             OPENTELEMETRY_MATLAB_INSTALL: "${{ github.workspace }}/otel_matlab_install"
-            OPENTELEMETRY_COLLECTOR_INSTALL: "${{ github.workspace }}/otelcol"
             SYSTEM_LIBSTDCPP_PATH: "/usr/lib/x86_64-linux-gnu/libstdc++.so.6"
         steps:
             - name: Download OpenTelemetry-Matlab source
@@ -17,11 +15,6 @@ jobs:
                 path: opentelemetry-matlab
             - name: Install MATLAB
               uses: matlab-actions/setup-matlab@v1
-            - name: Download OpenTelemetry Collector binary
-              run: |
-                  mkdir otelcol && cd otelcol
-                  wget https://github.com/open-telemetry/opentelemetry-collector-releases/releases/download/v0.75.0/otelcol_0.75.0_linux_amd64.tar.gz
-                  tar -xzf otelcol_0.75.0_linux_amd64.tar.gz
             - name: Build OpenTelemetry-Matlab
               run: |
                   cd opentelemetry-matlab