get back changes from testcenter-admin-app for backend 2.0.0

src/app/app.interceptor.ts

src/app/maindata.service.ts

src/app/superadmin/backend.service.ts

src/app/superadmin/superadmin.module.ts

src/app/superadmin/users/users.component.ts

src/app/superadmin/workspaces/workspaces.component.ts

src/app/sys-check/backend.service.ts

src/app/workspace-admin/backend.service.ts

src/app/workspace-admin/files/files.component.html

src/app/workspace-admin/files/files.component.ts

...iles/iqb-files/iqbFilesUpload/iqbFilesUpload.component.ts

src/app/workspace-admin/results/results.component.ts

src/app/workspace-admin/syscheck/syscheck.component.html

src/app/workspace-admin/syscheck/syscheck.component.ts

src/app/workspace-admin/workspace.component.ts

src/app/workspace-admin/workspace.interfaces.ts

src/app/workspace-admin/workspace.module.ts

src/app/workspace-admin/workspacedata.service.ts