Keeps initial product quantity unchanged

Previously, the product quantity was being decreased as new sales was being created. But the generated product report required to display the original product quantity.

After this changes, the original product quantity will remain untouched. A new variable will be introduced to track number of units sold.

Available units will be determined on the fly.

While editing product, the price and quantity can not be modified after more than 1 units has been sold.

Update UI

- Do not autofocus on filter text box

Remove secrets from git

- remove key.properties file and add it to gitignore
- Change the keystore secrets
- Update release-apk workflow
- Update version

Improve UX

- Remove filter box focus when tapped outside
- Set product list separator size to 1
- Make background of report pages white

Fix some issues with nav drawer, filter box, report pages etc

Version 1.2.0+3

Fix some issues and view

Add key.properties