Loosen pyquil requirements (quantumlib#5681)

Author: vtomole

cirq-rigetti/requirements.txt

@@ -1,19 +1 @@
-attrs~=20.3.0
-certifi~=2021.5.30
-h11~=0.9.0
-httpcore~=0.11.1
-httpx~=0.15.5
-idna~=2.10
-iso8601~=0.1.14
-pydantic~=1.8.2
-pyjwt~=1.7.1
-pyquil~=2.28.2; python_version < "3.7"
-pyquil~=3.0.0; python_version >= "3.7"
-python-dateutil~=2.8.1
-qcs-api-client~=0.8.0
-retrying~=1.3.3
-rfc3339~=6.2
-rfc3986~=1.5.0
-six~=1.16.0
-sniffio~=1.2.0
-toml~=0.10.2
+pyquil>=3.0.0