fix: revert auto-assign agents-access role enabled (#24170)

This reverts commit d4a9c63e91 (#23968).

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

coderd/users_test.go

@@ -829,35 +829,6 @@ func TestPostUsers(t *testing.T) {
 		assert.Equal(t, firstUser.OrganizationID, user.OrganizationIDs[0])
 	})
 
-	// CreateWithAgentsExperiment verifies that new users
-	// are auto-assigned the agents-access role when the
-	// experiment is enabled. The experiment-disabled case
-	// is implicitly covered by TestInitialRoles, which
-	// asserts exactly [owner] with no experiment — it
-	// would fail if agents-access leaked through.
-	t.Run("CreateWithAgentsExperiment", func(t *testing.T) {
-		t.Parallel()
-		dv := coderdtest.DeploymentValues(t)
-		dv.Experiments = []string{string(codersdk.ExperimentAgents)}
-		client := coderdtest.New(t, &coderdtest.Options{DeploymentValues: dv})
-		firstUser := coderdtest.CreateFirstUser(t, client)
-
-		ctx := testutil.Context(t, testutil.WaitLong)
-
-		user, err := client.CreateUserWithOrgs(ctx, codersdk.CreateUserRequestWithOrgs{
-			OrganizationIDs: []uuid.UUID{firstUser.OrganizationID},
-			Email:           "another@user.org",
-			Username:        "someone-else",
-			Password:        "SomeSecurePassword!",
-		})
-		require.NoError(t, err)
-
-		roles, err := client.UserRoles(ctx, user.Username)
-		require.NoError(t, err)
-		require.Contains(t, roles.Roles, codersdk.RoleAgentsAccess,
-			"new user should have agents-access role when agents experiment is enabled")
-	})
-
 	t.Run("CreateWithStatus", func(t *testing.T) {
 		t.Parallel()
 		auditor := audit.NewMock()