Bumb version for 5.3.4 bugfix release (#1815)

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "litgpt"
-version = "0.5.3.dev1"
+version = "0.5.4"
 description = "Hackable implementation of state-of-the-art open-source LLMs"
 authors = [
     { name = "Lightning AI", email = "[email protected]" },
@@ -35,7 +35,6 @@ test = [
     "transformers>=4.38.0",  # numerical comparisons
     "einops>=0.7.0",
     "protobuf>=4.23.4",
-    "lightning-thunder @ git+https://github.com/Lightning-AI/lightning-thunder/ ; python_version >= '3.10' and sys_platform == 'linux'",
 ]
 all = [
     "bitsandbytes==0.42.0",      # quantization