feat : (#31) add oauthUserInfo

Author: qkrwndnjs1075

src/main/kotlin/entry/dsm/gitauth/equusgithubauth/global/oauth/OAuth2UserInfo.kt

@@ -0,0 +1,8 @@
+package entry.dsm.gitauth.equusgithubauth.global.oauth
+
+interface OAuth2UserInfo {
+    fun getProvider(): String
+    fun getProviderId(): String
+    fun getEmail(): String
+    fun getName(): String
+}