Drop Python 3.7 support.

.github/workflows/test.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [ 3.7, 3.8, 3.9, "3.10" ]
+        python-version: [ 3.8, 3.9, "3.10" ]
 
     steps:
       - uses: actions/checkout@v2

README.rst

@@ -232,7 +232,7 @@ with Bluetooth.
    :alt: PyPi
    :target: https://pypi.python.org/pypi/hifiscan
 
-.. |PyVersion| image:: https://img.shields.io/badge/python-3.7+-blue.svg
+.. |PyVersion| image:: https://img.shields.io/badge/python-3.8+-blue.svg
    :alt:
 
 .. |Status| image:: https://img.shields.io/badge/status-stable-green.svg

setup.py

@@ -20,7 +20,6 @@ setup(
         'Intended Audience :: End Users/Desktop',
         'Topic :: Multimedia :: Sound/Audio :: Analysis',
         'License :: OSI Approved :: BSD License',
-        'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',
         'Programming Language :: Python :: 3.10',
@@ -30,6 +29,6 @@ setup(
     entry_points={
         'gui_scripts': ['hifiscan=hifiscan.app:main']
     },
-    python_requires=">=3.7",
+    python_requires=">=3.8",
     install_requires=['numpy', 'PyQt5', 'pyqtgraph', 'sounddevice']
 )