NO-JIRA Update development scripts & documentation

[7PH]

• Please explain your motives to contribute this change: what problem you are trying to fix, what improvement you are trying to make
• Use the following formatting style: SonarSource/sonar-developer-toolset
• Provide a unit test for any code you changed
• If there is a JIRA ticket available, please make your commits and pull request start with the ticket ID (VSTS-XXXX)

Summary

The developer guide was not working as expected when setting up a dev environment. Here are the changes:

• Minimum node requirement for development bumped to v14 from v6. Rationale:
  • npm 8 requires node >=12
  • sonar-scanner-npm requires node 14
  • • We could probably go as low as node 12 by using an older version of sonar-scanner-npm, but I figured out it's fine to enforce node 14 given it's the oldest node version in maintenance
• I felt free to update package-lock.json which is un-synced from package.json (eg running a cleaninstall on root folder was giving cipm can only install packages when your package.json and package-lock.json or npm-shrinkwrap.json are in sync. Please update your lock file with npm install before continuing
• Updated gulpfile to not expect cyclonedx to be present in the global PATH and instead use the binary from node

[mickael-caro-sonarsource]

LGTM