Rename namespace Function keyword to Functions to prevent errors

Signed-off-by: davidarendsen <davidarendsen@hey.com>

tests/Function/FromFunctionTest.php

@@ -1,38 +0,0 @@
-<?php
-declare(strict_types=1);
-
-use Arendsen\FluxQueryBuilder\Function\From;
-use PHPUnit\Framework\TestCase;
-
-final class FromFunctionTest extends TestCase {
-
-    /**
-     * @dataProvider somethingProvider
-     */
-    public function testSomething($settings, $query)
-    {
-        $expression = new From($settings);
-
-        $this->assertEquals($expression->__toString(), $query);
-    }
-
-    public function somethingProvider(): array
-    {
-        return [
-            'from bucket' => [
-                [
-                    'bucket' => 'test-bucket',
-                ],
-                'from(bucket: "test-bucket") '
-            ],
-            'from bucket and host' => [
-                [
-                    'bucket' => 'test-bucket',
-                    'host' => 'test',
-                ],
-                'from(bucket: "test-bucket", host: "test") '
-            ],
-        ];
-    }
-
-}