[chore] Test all contrib exporter groups in contrib-tests (#15681)

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#### Description

Contrib tests were not running against all modules since we at some
point created more module sets on contrib for exproters/

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Author: mx-psi

.github/workflows/contrib-tests.yml

@@ -51,6 +51,8 @@ jobs:
           - processor
           - exporter-0
           - exporter-1
+          - exporter-2
+          - exporter-3
           - extension
           - connector
           - internal