fix: WP_Styles::get_etag() should only take $load parameter

[justlevine]

Trac ticket: https://core.trac.wordpress.org/ticket/52217

This PR fixes an issue with the usage of the new $wp_style->get_etag() in load-styles.php, where the $wp_version is passed as the first arg instead of $load being used as the only arg.

While this issue was surfaced via PHPStan in #7619 (trac: https://core.trac.wordpress.org/ticket/61175 ), it should be remediated independently of that issue as it's a novel bug getting shipped in WP 6.7

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[github-actions]

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[mukeshpanchal27]

Nice catch!

[mukeshpanchal27]

Nice catch @justlevine, @SergeyBiryukov could you please take a look.

[swissspidy]

Added it https://core.trac.wordpress.org/ticket/61485

[swissspidy]

cc @peterwilsoncc

[github-actions]

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[mukeshpanchal27]

Committed in https://core.trac.wordpress.org/changeset/59341