[Tests] Silenced all deprecations in tests for 2.3
update required minimum TwigBridge version

To be able to use `Twig_SimpleFunction` in `AssetsExtension`, Twig has
to be present in version 1.12 or higher. The TwigBridge only enforces
this Twig version as of version 2.3.10.
minor #13033 [Tests] Silenced all deprecations in tests for 2.3 (saro0h)

This PR was merged into the 2.3 branch.

Discussion
----------

[Tests] Silenced all deprecations in tests for 2.3

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | ~
| License       | MIT
| Doc PR        | ~

Also removed src/Symfony/Component/Security/Core/Tests/Validator/Constraints/UserPasswordValidatorTest.php as it was not running at all.

Commits
-------

ef4ae63 [Tests] Silenced all deprecations in tests for 2.3
Merge branch '2.3' into 2.5

* 2.3:
  [Config] adds missing « use » statement for InvalidTypeException type hint in documentation.
  [Config] fixes broken unit test on ArrayNode class.
  fixed CS
  [Security] Delete old session on auth strategy migrate
  update required minimum TwigBridge version
  Very minor grammar fix in error message
  [Tests] Silenced all deprecations in tests for 2.3
  BinaryFileResponse - add missing newline
  fixed CS
  add a limit and a test to FlattenExceptionTest.
  CS: There should be no empty lines following phpdocs
  [FrameworkBundle] fix cache:clear command
  [2.3] Docblocks should not be followed by a blank line
  Fix return phpdoc
  [PropertyAccess] Added test to verify #5775 is fixed

Conflicts:
	src/Symfony/Bundle/TwigBundle/composer.json
	src/Symfony/Component/PropertyAccess/Tests/PropertyAccessorTest.php
	src/Symfony/Component/Security/Core/Tests/Validator/Constraints/UserPasswordValidatorTest.php
Merge branch '2.5' into 2.6

* 2.5:
  [Config] adds missing « use » statement for InvalidTypeException type hint in documentation.
  [Config] fixes broken unit test on ArrayNode class.
  fixed CS
  [Security] Delete old session on auth strategy migrate
  update required minimum TwigBridge version
  Very minor grammar fix in error message
  [Tests] Silenced all deprecations in tests for 2.3
  BinaryFileResponse - add missing newline
  fixed CS
  add a limit and a test to FlattenExceptionTest.
  CS: There should be no empty lines following phpdocs
  [FrameworkBundle] fix cache:clear command
  [2.3] Docblocks should not be followed by a blank line
  Fix return phpdoc
  [PropertyAccess] Added test to verify #5775 is fixed