Document all supported SpringProperties keys in the reference manual

[sbrannen]

Overview

As a follow-up to #26492, we should document all known, supported properties that can be used with SpringProperties -- for example, by adding a dedicated section or appendix to the reference manual.

Initial Analysis

We currently support the following Spring properties within the core Spring Framework.

• spring.beaninfo.ignore
• spring.expression.compiler.mode
• spring.getenv.ignore
• spring.index.ignore
• spring.jdbc.getParameterType.ignore
• spring.jndi.ignore
• spring.objenesis.ignore
• spring.test.constructor.autowire.mode
• spring.test.context.cache.maxSize
• spring.test.enclosing.configuration

None of these (other than the ones from spring-test) are documented anywhere in the reference manual.

NOTE: Although spring.xml.ignore and spring.spel.ignore are currently used by the framework, they are not officially supported and are subject to change (name and/or semantics) over time.

Deliverables

• Assemble a list/table of supported Spring properties and introduce a new section in the reference manual (perhaps an appendix of sorts) that briefly describes what they are for and links to Javadoc or an appropriate section of the reference manual.