Admin dashboard best seller time period documentation is incorrect

Issue in ./help/getting-started/admin-dashboard.md

The documentation says "The five best-selling products during the specified time period." however, there is no time period to specify. When comparing this report with the Reports > Products > Best sellers, we can see that the top 5 products are from all time.

The documentation should say "best seller of all time" without a "the time period selected"

The same should be checked for most viewed products, new customers and customers.

Open help/getting-started/admin-dashboard.md and locate the best-selling products description. Compare the wording with the Reports > Products > Best sellers behavior, then check the descriptions for most viewed products, new customers, and customers; done means the time-period wording is removed or corrected to reflect all-time data.

Written by the indexing model from the issue text.