CI: Disable mod_prometheus testing

Right now compilation fails due to many:

.../prometheus-4.11.0/src/metrics/prometheus_quantile_summary.erl:67:14:
can't find include lib "quantile_estimator/include/quantile_estimator.hrl"
%   67| -include_lib("quantile_estimator/include/quantile_estimator.hrl").

.github/workflows/ci.yml

@@ -102,6 +102,9 @@ jobs:
     - name: Disable mod_captcha_rust testing
       run: sed -i '/mod_captcha_rust/d' modules_available.txt
 
+    - name: Disable mod_prometheus testing
+      run: sed -i '/mod_prometheus/d' modules_available.txt
+
     - name: Disable mod_s3_upload testing with old OTP
       if: matrix.elixir < '1.16'
       run: sed -i '/mod_s3_upload/d' modules_available.txt