Update requirements.txt

Ran into a pydantic-related error when installing with the previous requirements.txt file.

Probably best to keep this minimal to avoid any dependency issues.

prompt-engineering/requirements.txt

@@ -1,14 +1 @@
-annotated-types==0.6.0
-anyio==4.3.0
-certifi==2024.2.2
-distro==1.9.0
-h11==0.14.0
-httpcore==1.0.4
-httpx==0.27.0
-idna==3.6
 openai==1.13.3
-pydantic==2.6.3
-pydantic-core==2.16.3
-sniffio==1.3.1
-tqdm==4.66.2
-typing-extensions==4.10.0