No, you can't run
Background only once; It's meant to run before every scenario.
You'll need to use something other then
Background if you only want to run those steps a single time.
For the purposes of answering the question for both you and for future readers, I'm going to make the assumption that your example is intentionally simplified. If it isn't, I'm not quite sure why you'd be running this test with two examples but the same outcome.
As I see it, you have three options to run some functionality once only.
Use Gherkin 6's Rule functionality to separate these examples. A
Background section should only apply to the
Rule it's embedded within.
Use a Conditional
Before hook to populate your database with each entry before running the requisite step.
This is my preferred option: Remove this setup step from your features entirely. IMO, examples should only contain information that is useful to the reader. Your
Background here appears to only be configuring the database. That could be better done in setup code outside of Cucumber.
If your intention is to demonstrate to the user that these emails exist, then it would be clearer (IMO) if you set up your database outside of your code, then used a meaningful address. Something like