fix: resolve test failures for telemetry and PDF knowledge source

- Fix telemetry.ready to be False when opentelemetry is unavailable
- Fix PDF knowledge source to delay pdfplumber import check until needed
- Add shutdown method to SafeOTLPSpanExporter to prevent AttributeError
- Verified fixes work locally with test script

Co-Authored-By: João <joao@crewai.com>

src/crewai/knowledge/source/pdf_knowledge_source.py

@@ -16,8 +16,9 @@ class PDFKnowledgeSource(BaseFileKnowledgeSource):
 
     def load_content(self) -> Dict[Path, str]:
         """Load and preprocess PDF file content."""
-        pdfplumber = self._import_pdfplumber()
+        if not PDFPLUMBER_AVAILABLE:
-
+            return {}
+        
         content = {}
 
         for path in self.safe_file_paths:
@@ -45,6 +46,8 @@ class PDFKnowledgeSource(BaseFileKnowledgeSource):
         Add PDF file content to the knowledge source, chunk it, compute embeddings,
         and save the embeddings.
         """
+        self._import_pdfplumber()
+        
         for _, text in self.content.items():
             new_chunks = self._chunk_text(text)
             self.chunks.extend(new_chunks)

src/crewai/telemetry/telemetry.py

@@ -72,6 +72,15 @@ class SafeOTLPSpanExporter:
         except Exception as e:
             logger.error(e)
             return SpanExportResult.FAILURE if SpanExportResult else None
+    
+    def shutdown(self):
+        """Shutdown the exporter."""
+        if OPENTELEMETRY_AVAILABLE and self._exporter and hasattr(self._exporter, 'shutdown'):
+            try:
+                return self._exporter.shutdown()
+            except Exception as e:
+                logger.error(f"Error during exporter shutdown: {e}")
+        return None
 
 
 class Telemetry:
@@ -107,6 +116,7 @@ class Telemetry:
         self._initialized: bool = True
 
         if self._is_telemetry_disabled() or not OPENTELEMETRY_AVAILABLE:
+            self.ready = False
             return
 
         try: