feat: filter users by github user id in the users list CLI command (#17029)

Add the `--github-user-id` option to `coder users list`, which makes the
command only return users with a matching GitHub user id. This will
enable https://github.com/coder/start-workspace-action to find a Coder
user that corresponds to a GitHub user requesting to start a workspace.

coderd/users_test.go

@@ -2,6 +2,7 @@ package coderd_test
 
 import (
 	"context"
+	"database/sql"
 	"fmt"
 	"net/http"
 	"slices"
@@ -1873,6 +1874,33 @@ func TestGetUsers(t *testing.T) {
 		require.NoError(t, err)
 		require.ElementsMatch(t, active, res.Users)
 	})
+	t.Run("GithubComUserID", func(t *testing.T) {
+		t.Parallel()
+		ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+		defer cancel()
+
+		client, db := coderdtest.NewWithDatabase(t, nil)
+		first := coderdtest.CreateFirstUser(t, client)
+		_ = dbgen.User(t, db, database.User{
+			Email:    "test2@coder.com",
+			Username: "test2",
+		})
+		// nolint:gocritic // Unit test
+		err := db.UpdateUserGithubComUserID(dbauthz.AsSystemRestricted(ctx), database.UpdateUserGithubComUserIDParams{
+			ID: first.UserID,
+			GithubComUserID: sql.NullInt64{
+				Int64: 123,
+				Valid: true,
+			},
+		})
+		require.NoError(t, err)
+		res, err := client.Users(ctx, codersdk.UsersRequest{
+			SearchQuery: "github_com_user_id:123",
+		})
+		require.NoError(t, err)
+		require.Len(t, res.Users, 1)
+		require.Equal(t, res.Users[0].ID, first.UserID)
+	})
 }
 
 func TestGetUsersPagination(t *testing.T) {