fix zipkin tag value type

Author: nekufa

src/Tracing/Exporter/ZipkinExporter.php

@@ -56,10 +56,7 @@ private function convertAttributes(array $attributes): array
         $tags = [];
 
         foreach ($attributes as $k => $v) {
-            if (is_bool($v)) {
-                $v = (string) $v;
-            }
-            $tags[$k] = $v;
+            $tags[$k] = (string) $v;
         }
 
         return $tags;

tests/Tracing/TransportTest.php

@@ -19,6 +19,7 @@ public function testZipkin()
         $span = $tracer->getActiveSpan();
         $event = $span->addEvent('hello world');
         $span->setAttribute('nick', 'nekufa');
+        $span->setAttribute('counter', 27);
         $span->end();
 
         $client = new MockHttpClient([
@@ -38,8 +39,9 @@ function ($method, $url, $options) use ($span, $event) {
                 $this->assertSame($row->duration, (int) $duration);
 
                 $this->assertEquals($row->localEndpoint, (object) [ 'serviceName' => 'tester' ]);
-                $this->assertCount(1, get_object_vars($row->tags));
+                $this->assertCount(2, get_object_vars($row->tags));
                 $this->assertSame($row->tags->nick, 'nekufa');
+                $this->assertSame($row->tags->counter, '27');
                 $this->assertCount(1, $row->annotations);
 
                 [ $annotation ] = $row->annotations;