Previously, when using SpringApplication.from() any additional
sources configured using with() would be applied to every
SpringApplication that was created within the scope of the call to
run(). This caused problems with Spring Cloud's bootstrap context
where the additional sources would be applied to both the user's
application and to the boostrap context's application.
This commit updates the hook that's used to apply the additional
sources so that it's only applied once. This results in the
additional sources only being added to the first SpringApplication
that is run.
Closes gh-35873
1652c27b3c