SpringBoot Support for Base64 encoded p12 keystore using the ssl bundle configuration

I've added support for Base64 encoded p12 formatted keystores. This is my backing StackOverflow question

Comment From: pivotal-cla

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Comment From: pivotal-cla

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Comment From: scottfrederick

@erwinc1 Thanks very much for the suggestion. We agree this is something that we'd like Spring Boot to support. However, we'd like to take a different approach to the problem that would allow us to apply the same pattern to other places where file resources are currently supported in configuration properties instead of just making your suggested change to SSL bundle JKS keystores. I've opened #36033 to capture this.