Fix: visits-service scale down to one, not zero

[haoozhang]

Purpose

If visits-service scales down to zero, we will meet the error 503 Service Unavailable when calling it via api-gateway. This is because that the spring cloud gateway internally use Eureka Service Discovery to discover the instance. When scaled to zero, it will be considered as no such instance.

Does this introduce a breaking change?

[ ] Yes
[ ] No

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

How to Test

• Get the code

git clone [repo-address]
cd [repo-name]
git checkout [branch-name]
npm install

• Test the code

What to Check

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Other Information