hlx up does not reload changes of local JS required files

[kptdobe]

Description
If you require a local JS file from a pre.js, the changes in that local JS file will not be reloaded after a change, even though hlx up says it has rebuilt the project files.

To Reproduce
Steps to reproduce the behavior:

1. hlx demo test
2. cd test/src
3. Create a util.js file with content (completely arbitrary):

module.exports.log = function(msg) {
    console.log(`LOG: ${msg}`);
};

4. Edit html.pre.js:

const util = require('./util');

function pre(payload) {
  util.log('Hello world');
}

module.exports.pre = pre;

5. Run hlx up
6. See the terminal log output: LOG: Hello world
7. Edit util.js and change the log output:

    console.log(`This is a nicer log prefix: ${msg}`);

8. Save and see the terminal log output: Rebuilding project files...done Xms (changes have been detected
9. Reload the page

-> See the terminal log output: LOG: Hello world. It should be This is a nicer log prefix: Hello world.

The only way to get the latest modification is to restart hlx up!

Expected behavior
Changes are reloaded.

Version:
run: $ hlx --version
v0.13.11-pre.10

[tripodsan]

should be possible to easily delete all modified modules from the resolver cache.