Document or take into account StubPropertySource

[FBibonne]

According to StubPropertySource javadoc, some properties like servlet init params are binded lately : the lib doe not take into account for the moment :

• Display it if it is possible
• At least, document this

[FBibonne]

NB : servlet relative stub property sources are logged :

2025-07-30T09:53:05.338+02:00 DEBUG 173246 --- [           main] i.g.f.s.b.p.PropertiesLogger             : StubPropertySource {name='servletConfigInitParams'} is a stub property source : it does not contain properties : will be ignored
2025-07-30T09:53:05.338+02:00 DEBUG 173246 --- [           main] i.g.f.s.b.p.PropertiesLogger             : StubPropertySource {name='servletContextInitParams'} is a stub property source : it does not contain properties : will be ignored
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