[DependencyInjection] made some perf improvements

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | yes
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | n/a
| License       | MIT
| Doc PR        | n/a

This PR optimizes the creation of dumped containers drastically (thanks @jpauli for the hint).

The Container class generated by the PHP dumper does not include the `getDefaultParameters()` method anymore. It does not seem like a big deal to me as I fail to see a use case where someone would override this method.

is the static property needed in case of non-frozen containers ? would it improve perf in this case ? The static array will need to be copied as soon as you manipulate parameters.

I know that this is kind of an edge case given that Symfony always freezes the container before dumping it (I'm not even sure there is  valid use case for dumping a non-frozen container, given that parameters used in service definitions will always be inlined, so changing them in the ParameterBag will be useless for most of them)