Update version for the next release (v1.8.0)

[meili-bot]

This PR is auto-generated.

The automated script updates the version of meilisearch-php to a new version: "v1.8.0"

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This version introduces features released on Meilisearch v1.8.0 🎉 Check out the changelog of Meilisearch v1.8.0 for more information on the changes.

🚀 Enhancements

• Add support for the new setting: searchCutoffMs (https://github.com/meilisearch/meilisearch-php/pull/636) @/brunoocasali

$client->index('books')->getSearchCutoffMs();
$client->index('books')->updateSearchCutoffMs(150);
$client->index('books')->resetSearchCutoffMs();

• Add getSemanticHitCount() method to retrieve how many results were found because of the semantic query. https://github.com/meilisearch/meilisearch-php/pull/639 @brunoocasali

⚙️ Maintenance/misc

• Add missing $ to documentation code sample (https://github.com/meilisearch/meilisearch-php/pull/633) @/guimachiavelli