Update dependency composer/installers to v1.11.0 (9.x-postgres)

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
composer/installers (source)	require	minor	1.10.0 -> 1.11.0

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Release Notes

composer/installers

### [`v1.11.0`](https://togithub.com/composer/installers/blob/master/CHANGELOG.md#v1110---2021-04-28) [Compare Source](https://togithub.com/composer/installers/compare/v1.10.0...v1.11.0) ##### Added - Added installer for TastyIgniter extensions and themes [#​478](https://togithub.com/composer/installers/pull/478). - Added installers for Winter CMS [#​480](https://togithub.com/composer/installers/pull/480), [#​481](https://togithub.com/composer/installers/pull/481). - Added installer for Miaoxing plugin [#​482](https://togithub.com/composer/installers/pull/482).

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