Bump Python and Ubuntu version in README.md (#213)

Author: weiliw-amz

README.md

@@ -29,15 +29,15 @@ Given an input, PECOS identifies a small set (10-100) of relevant outputs from a
 
 ## Requirements and Installation
 
-* Python (>=3.6, <=3.9)
+* Python (3.7, 3.8, 3.9, 3.10)
 * Pip (>=19.3)
 
 See other dependencies in [`setup.py`](https://github.com/amzn/pecos/blob/mainline/setup.py#L135)
 You should install PECOS in a [virtual environment](https://docs.python.org/3/library/venv.html).
 If you're unfamiliar with Python virtual environments, check out the [user guide](https://packaging.python.org/guides/installing-using-pip-and-virtual-environments/).
 
 ### Supporting Platforms
-* Ubuntu 18.04 and 20.04
+* Ubuntu 20.04 and 22.04
 * Amazon Linux 2
 
 ### Installation from Wheel
@@ -51,20 +51,20 @@ python3 -m pip install libpecos
 ### Installation from Source
 
 #### Prerequisite builder tools
-* For Ubuntu (18.04, 20.04):
+* For Ubuntu (20.04, 22.04):
 ``` bash
 sudo apt-get update && sudo apt-get install -y build-essential git python3 python3-distutils python3-venv
 ```
-* For Amazon Linux 2 Image:
+* For Amazon Linux 2:
 ``` bash
-sudo yum -y install python3 python3-devel python3-distutils python3-venv && sudo yum -y groupinstall 'Development Tools' 
+sudo yum -y install python3 python3-devel python3-distutils python3-venv && sudo yum -y groupinstall 'Development Tools'
 ```
 One needs to install at least one BLAS library to compile PECOS, e.g. `OpenBLAS`:
-* For Ubuntu (18.04, 20.04):
+* For Ubuntu (20.04, 22.04):
 ``` bash
 sudo apt-get install -y libopenblas-dev
 ```
-* For Amazon Linux 2 Image and AMI:
+* For Amazon Linux 2:
 ``` bash
 sudo amazon-linux-extras install epel -y
 sudo yum install openblas-devel -y