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/headscale/templates/config.yaml b/charts/headscale/templates/config.yaml
index 85d8b79..7c007ba 100644
--- a/charts/headscale/templates/config.yaml
+++ b/charts/headscale/templates/config.yaml
@@ -273,7 +273,7 @@
         # OpenID Connect
         oidc:
           only_start_if_oidc_is_available: true
-          issuer: {{ .Values.oauth2.hydraPublic }}
+          issuer: {{ .Values.oauth2.issuer }}
           client_id: {{`{{ .client_id }}`}}
           client_secret: {{`{{ .client_secret }}`}}
           scope: ["openid", "profile", "email"]