fix: Update noxfile and dependencies

Update dependencies, update minimal python version to 3.6.1
Fix noxfile, generate constraint file using constraint format add
`--without-hashes` option to be able to install dependencies, see:
python-poetry/poetry#3472 (comment)

Update python interpreter to test.

.github/workflows/tests.yml

@@ -6,7 +6,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ['3.6', '3.7', '3.8']
+        python-version: ['3.7', '3.8', '3.9', '3.10']
     name: Python ${{ matrix.python-version }}
     steps:
     - uses: actions/checkout@v2

noxfile.py

@@ -4,7 +4,7 @@
 import nox
 from nox.sessions import Session
 
-PYTHON_VERSIONS = ("3.8", "3.7", "3.6")
+PYTHON_VERSIONS = ("3.10", "3.9", "3.8", "3.7", "3.6")
 LOCATIONS = ("noxfile.py", "tests", "sockit")
 
 nox.options.sessions = ("lint", "mypy", "pytype", "tests")
@@ -17,8 +17,10 @@ def install_with_constraints(
         session.run(
             "poetry",
             "export",
-            "--dev",
-            "--format=requirements.txt",
+            "--with",
+            "dev",
+            "--without-hashes",
+            "--format=constraints.txt",
             f"--output={requirements.name}",
             external=True,
         )
@@ -28,7 +30,7 @@ def install_with_constraints(
 @nox.session(python=PYTHON_VERSIONS)
 def tests(session: Session) -> None:
     args = session.posargs or ["--cov"]
-    session.run("poetry", "install", "--no-dev", external=True)
+    session.run("poetry", "install", "--only", "main", external=True)
     install_with_constraints(session, "coverage[toml]", "pytest", "pytest-cov")
     session.run("pytest", *args)