fix alpha config example

contrib/local-environment/oauth2-proxy-alpha-config.cfg

@@ -1,5 +1,4 @@
-http_address="0.0.0.0:4180"
 cookie_secret="OQINaROshtE9TcZkNAm-5Zs2Pv3xaWytBmc5W7sPX7w="
 email_domains="example.com"
 cookie_secure="false"
-redirect_url="http://localhost:4180/oauth2/callback"
+redirect_url="http://oauth2-proxy.localtest.me:4180/oauth2/callback"

contrib/local-environment/oauth2-proxy-alpha-config.yaml

@@ -1,22 +1,30 @@
+server:
+  bindAddress: "0.0.0.0:4180"
+upstreamConfig:
   upstreams:
     - id: httpbin
       path: /
-    uri: http://httpbin
+      uri: http://httpbin.localtest.me:8080
 injectRequestHeaders:
   - name: X-Forwarded-Groups
     values:
-  - claim: groups
+      - claimSource:
+          claim: groups
   - name: X-Forwarded-User
     values:
-  -   claim: user
+      - claimSource:
+          claim: user
   - name: X-Forwarded-Email
     values:
-  - claim: email
+      - claimSource:
+          claim: email
   - name: X-Forwarded-Preferred-Username
     values:
-  - claim: preferred_username
+      - claimSource:
+          claim: preferred_username
 providers:
-- provider: oidc
+  - id: oidc
+    provider: oidc
     clientSecret: b2F1dGgyLXByb3h5LWNsaWVudC1zZWNyZXQK
     clientID: oauth2-proxy
     oidcConfig: