FEAT #15420 TIME 4 upgrade to angular 11

.browserslistrc

angular.json

package.json

src/frontend/app/app-routing.module.ts

src/frontend/app/app.component.html

src/frontend/app/app.module.ts

src/frontend/app/document/document.component.ts

src/frontend/app/service/signatures.service.ts

src/frontend/core/.browserslistrc

tsconfig.json

tslint.json