feat:added buyer update form

package-lock.json

src/app/app.module.ts

src/app/components/buyer/buyer.component.html

src/app/components/buyer/buyer.component.ts

.../forms/buyer-update-form/buyer-update-form.component.html

.../forms/buyer-update-form/buyer-update-form.component.scss

...ts/forms/buyer-update-form/buyer-update-form.component.ts

src/app/components/forms/login-form/login-form.component.ts

src/styles.scss