ReactUI Add info to increase heap when building ui & clarify version of node/npm

[planetf1]

To avoid this see ci/cd build at https://github.com/odpi/egeria-react-ui/blob/main/.github/workflows/node-build.yml

We need to add this setting into the doc ie as environment variable or parameter on the build

NODE_OPTIONS="--max_old_space_size=6144"

For example

export NODE_OPTIONS="--max_old_space_size=6144"
npm run build
...

This should be referenced from https://egeria-project.org/user-interfaces/ecosystem/configure-and-run-presentation-server/

More detail on options at https://nodejs.org/api/cli.html#cli_node_options_options

[planetf1]

The build instructions also need to specify the correct version of node/npm to use (x or higher most likely), or point the user back to the source code where that is specified, or otherwise how to find out.

NOTE: The current build in egeria-react-ui under .github/workflows/node_build.yaml is set to use node 14.
If this is not correct, please update to be consistent