Bump sabberworm/php-css-parser from 8.5.1 to 8.6.0 #1647

Job	Run time
Pre run	1m 45s
Lint: JS	1m 2s
Unit test: JS	1m 0s
Lint: PHP	21s
Lint: CSS	0s
E2E test: JS (1, 2)	51s
E2E test: JS (2, 2)	52s
Unit test: PHP 8.0, WP latest	44s
Build: ${{ matrix.build }} build ZIP	0s
Unit test: PHP 8.3, WP trunk	35s
Unit test: PHP 8.2, WP trunk	54s
Unit test: PHP 8.1, WP trunk	35s
Feature tests: PHP 7.4, WP latest	36s
Static Analysis: PHP	12s
Unit test: PHP 8.0, WP trunk	37s
Feature tests: PHP 8.3, WP trunk	42s
Unit test (with coverage): PHP 8.0, WP latest	41s
Feature tests: PHP 8.2, WP trunk	40s
Unit test: PHP 8.0, WP latest	34s
Feature tests: PHP 8.1, WP trunk	39s
Unit test: PHP 7.4, WP latest	34s
Feature tests: PHP 8.0, WP latest	33s
Unit test: PHP 7.4, WP latest	34s
Feature tests: PHP 7.4, WP 6.3	45s
Unit test: PHP 7.4, WP 6.3	37s
Unit test: PHP 7.4, WP 6.3	36s
Upload plugin ZIPs to Google Cloud Storage	0s
Comment on PR with links to plugin ZIPs	0s
	16m 59s

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