Enhancements: Timeline Preview changes

Adds Timeline Preview changes to SDK

• sets headers from URL when browser is detected
• sets headers from query object when livePreviewQuery function is executed

Feat: updateAssetURL method added

Merge pull request #179 from contentstack/next

updateAssetURL method added

fixes

Hotfix moving slack/bolt to devDependency

Enhancements

Query operators implementation-3

Enhancements

Query operators implementation-2

Enhancements

Query operators implementation

Fixes

Update Utils SDK dependency version

Enhancement

Live preview support 1.0 and 2.0

Fix: build scripts on release

• Includes adding of prepare script to build package

v3.19.0

• live preview support both 1.0 and 2.0
• fix for ESM module cannot use module.exports issue react-native and nativescript builds