docs: Add template for `perun_connector`

config_templates/perun_connector.yaml

+---
+
+attributes_manager_config:
+  adapters:
+    - type: "openApi"
+      priority: 1
+      host: "https://api-dev.perun-aai.org/ba/rpc"
+      auth_type: "BasicAuth"
+      username: "sampleuser"
+      password: "samplepassword"
+      rp_id_attribute: "urn:perun:facility:attribute-def:def:rpIdentifier"
+attributes_map:
+  "urn:perun:user:attribute-def:def:mfaEnforceSettings:sampleNamespace":
+    id: 1
+    type: "java.lang.String"
+    ldap:
+  "urn:perun:user:attribute-def:def:mfaTokenTypes:sampleNamespace":
+    id: 2
+    type: "java.util.ArrayList"
+    ldap:
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