fix(deps): update dependency symfony/flex to v1.16.3

This MR contains the following updates:

Package	Type	Update	Change
symfony/flex	require	minor	1.15.4 -> 1.16.3

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Release Notes

symfony/flex

v1.16.3

Compare Source

v1.16.2

Compare Source

v1.16.1

Compare Source

v1.16.0

Compare Source

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