Upgrade dependencies to symfony/* 7.0 #74

Job	Run time
Json validation	11s
Tests - PHP 7.4 - Deps lowest - PHPUnit 8.5.19	25s
Tests - PHP 7.4 - Deps lowest - PHPUnit 9.0	28s
Tests - PHP 7.4 - Deps lowest - PHPUnit 9.3	30s
Tests - PHP 7.4 - Deps lowest - PHPUnit 9.5	26s
Tests - PHP 7.4 - Deps highest - PHPUnit 9.0	22s
Tests - PHP 7.4 - Deps highest - PHPUnit 9.3	22s
Tests - PHP 7.4 - Deps highest - PHPUnit 9.5	22s
Tests - PHP 8.0 - Deps lowest - PHPUnit 8.5.19	22s
Tests - PHP 8.0 - Deps lowest - PHPUnit 9.0	29s
Tests - PHP 8.0 - Deps lowest - PHPUnit 9.3	22s
Tests - PHP 8.0 - Deps lowest - PHPUnit 9.5	35s
Tests - PHP 8.0 - Deps highest - PHPUnit 9.0	25s
Tests - PHP 8.0 - Deps highest - PHPUnit 9.3	35s
Tests - PHP 8.0 - Deps highest - PHPUnit 9.5	23s
Tests - PHP 8.1 - Deps lowest - PHPUnit 8.5.19	23s
Tests - PHP 8.1 - Deps lowest - PHPUnit 9.0	28s
Tests - PHP 8.1 - Deps lowest - PHPUnit 9.3	24s
Tests - PHP 8.1 - Deps lowest - PHPUnit 9.5	24s
Tests - PHP 8.1 - Deps highest - PHPUnit 9.0	21s
Tests - PHP 8.1 - Deps highest - PHPUnit 9.3	23s
Tests - PHP 8.1 - Deps highest - PHPUnit 9.5	30s
	9m 10s

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