fix: update dependency specifier for speechmatics-voice

Change the version specifier from >=0.2.8 to ~=0.2.8 for the
speechmatics-voice package to ensure compatibility with future
patch versions.

pyproject.toml

@@ -114,7 +114,7 @@ silero = [ "onnxruntime~=1.23.2" ]
 simli = [ "simli-ai~=1.0.3"]
 soniox = [ "pipecat-ai[websockets-base]" ]
 soundfile = [ "soundfile~=0.13.1" ]
-speechmatics = [ "speechmatics-voice[smart]>=0.2.8" ]
+speechmatics = [ "speechmatics-voice[smart]~=0.2.8" ]
 strands = [ "strands-agents>=1.9.1,<2" ]
 tavus=[]
 together = []