Bump Python 3.7.6 -> 3.7.7, 3.8.1 -> 3.8.2

CHANGES.rst

@@ -11,7 +11,7 @@ Platform and Packaging Updates
 ------------------------------
 
 - Python version updates: gevent is now tested with CPython 3.6.10,
-  3.7.6 and 3.8.1. It is also tested with PyPy2 7.3 and PyPy 3.6
+  3.7.7 and 3.8.2. It is also tested with PyPy2 7.3 and PyPy 3.6
   7.3.
 
 - The include directories used to compile the C extensions have been

scripts/install.sh

@@ -108,10 +108,10 @@ for var in "$@"; do
             install 3.6.10 python3.6 3.6.d
             ;;
         3.7)
-            install 3.7.6 python3.7 3.7.d
+            install 3.7.7 python3.7 3.7.d
             ;;
         3.8)
-            install 3.8.1 python3.8 3.8.d
+            install 3.8.2 python3.8 3.8.d
             ;;
         pypy2.7)
             install pypy2.7-7.3.0 pypy2.7 pypy2.7.d