[FrameworkBundle] Remove DI, Entity and Kernel exclusion from the default services file

[Jean-Beru]

Since symfony/symfony#59987 and according to the recipe, the default config/services.yaml does not exclude DI, Entity and Kernel file/folders anymore.

[javiereguiluz]

Thanks Hubert. This was good, but while merging we did some minor tweaks:

• We removed the exclude config in another doc page
• We added an example of using exclude because otherwise this is not shown anywhere ... and this feature can still be useful in some cases

See 59fd3a3

[Jean-Beru]

Thanks Hubert. This was good, but while merging we did some minor tweaks:

• We removed the exclude config in another doc page
• We added an example of using exclude because otherwise this is not shown anywhere ... and this feature can still be useful in some cases

See 59fd3a3

Good catch. Thanks @javiereguiluz