[BUG]: Fix Typo in `searchResultClassName` Configuration Key

[BreathCodeFlow]

Description

There is a typo in the configuration key for searchResultClassName in the code. The key contains an unintended trailing space ('searchResultClassName ') which leads to incorrect behavior when retrieving the configuration value.

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Steps to Reproduce

ext-solr/Classes/Domain/Search/ResultSet/Result/SearchResultBuilder.php

Line 48 in b6bfad8

return $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['solr']['searchResultClassName '] ?? SearchResult::class;

1. Configure the searchResultClassName in TYPO3_CONF_VARS:

   $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['solr']['searchResultClassName'] = \CustomNamespace\CustomSearchResult::class;

2. Attempt to use the custom class in the Solr integration.
3. The custom class is not used because the incorrect key ('searchResultClassName ') is being checked.

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Expected Behavior

The code should check for the key without the trailing space ('searchResultClassName') and fall back to the default SearchResult::class if not set.

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Actual Behavior

The code currently checks for the key with a trailing space ('searchResultClassName '), which causes the custom configuration to be ignored.

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Proposed Fix

Replace the following line:

return $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['solr']['searchResultClassName '] ?? SearchResult::class;

With:

return $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['solr']['searchResultClassName'] ?? SearchResult::class;