Update CI (#621)

### Summary

1. Don't run the tests on push (shouldn't need it since we always make a
PR)
2. Build the website in the tests to make sure it compiles without error
(we should add some tests to make sure it looks ok too, but that's out
of scope of this PR).

.github/workflows/tests.yml

@@ -1,6 +1,6 @@
 name: Sourcecode tests
 
-on: [push, pull_request, workflow_dispatch]
+on: [pull_request, workflow_dispatch]
 
 jobs:
   lint:
@@ -46,6 +46,8 @@ jobs:
       run: |
         unset CI
         tox ${{ env.TOX_ENV }}
+    - name: Build website
+      run: tox -e website
   coverage:
     runs-on: ubuntu-latest
     steps:

ecosystem/resources/members/qiskit-qulacs.toml

@@ -6,7 +6,7 @@ contact_info = "[email protected]"
 alternatives = "_No response_"
 affiliations = "Supported by the Unitary Fund microgrant program: https://unitary.fund/grants/"
 labels = [ "Circuit simulator", "Converter", "Provider",]
-groups = "provider"
+group = "provider"
 tier = "Community"
 website = "https://qiskit-qulacs.netlify.app/"
 tests_results = []