Use userName instead of username for Identity's FindByUsernameAsync.

Fix #5897

modules/identity/src/Volo.Abp.Identity.Application.Contracts/Volo/Abp/Identity/IIdentityUserAppService.cs

@@ -19,7 +19,7 @@ namespace Volo.Abp.Identity
 
         Task UpdateRolesAsync(Guid id, IdentityUserUpdateRolesDto input);
 
-        Task<IdentityUserDto> FindByUsernameAsync(string username);
+        Task<IdentityUserDto> FindByUsernameAsync(string userName);
 
         Task<IdentityUserDto> FindByEmailAsync(string email);
     }

modules/identity/src/Volo.Abp.Identity.Application/Volo/Abp/Identity/IdentityUserAppService.cs

@@ -135,10 +135,10 @@ namespace Volo.Abp.Identity
         }
 
         [Authorize(IdentityPermissions.Users.Default)]
-        public virtual async Task<IdentityUserDto> FindByUsernameAsync(string username)
+        public virtual async Task<IdentityUserDto> FindByUsernameAsync(string userName)
         {
             return ObjectMapper.Map<IdentityUser, IdentityUserDto>(
-                await UserManager.FindByNameAsync(username)
+                await UserManager.FindByNameAsync(userName)
             );
         }