oauth2-client: migrate apps to use oauth2-client helm chart (#90)

* headscale: use oauth2-client helm chart

* pihole: use oauth2-client helm chart

* matrix: use oauth2-client helm chart

* oauth2: pass issuer address to pihole, headscale and matrix apps

* pihole: fix secret name

* matrix: fix version to v1.98.0

* headscale: make oauth2-client depend on auth release

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Co-authored-by: Giorgi Lekveishvili <lekva@gl-mbp-m1-max.local>
diff --git a/charts/matrix/values.yaml b/charts/matrix/values.yaml
index 64d2e90..5d57ae0 100644
--- a/charts/matrix/values.yaml
+++ b/charts/matrix/values.yaml
@@ -5,8 +5,7 @@
 domain: example.com
 subdomain: matrix
 oauth2:
-  hydraAdmin: http://hydra-admin
-  hydraPublic: https://hydra.example.com
+  issuer: https://oidc-issuer.example.com
   secretName: oauth2-client
 postgresql:
   host: postgresql