🗑️ Setup.py: Ended support for Python 3.7.x legacies (Fixes #48)

- 🏗️ Increased `python_requires` to `3.8` and above.
- 🔥  Removed depreciated Python-3.7 from metadata.

setup.py

@@ -90,13 +90,12 @@
         "Intended Audience :: Science/Research",
         "Intended Audience :: Education",
         "License :: OSI Approved :: Apache Software License",
-        "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
     ],
-    python_requires=">=3.7",
+    python_requires=">=3.8",
     scripts=[],
     project_urls={
         "Bug Reports": "https://github.com/abhiTronix/deffcode/issues",