Update pre-request scripts to mitigate concurrent modification issue while removing blank headers

[dlh3]

Description

In Postman 10.7.1 for MacOS, pm.request.headers.each() fails when removing headers while iterating over them:

TypeError: Cannot read properties of undefined (reading 'value')

Using Request.forEachHeader() avoids that pitfall. Other options would be operating on pm.request.headers.members, or calling all() or map() before each(), since either would result in an independent list of headers.

For reference, Request.forEachHeader() internally calls pm.request.headers.all().each(callback).

Related Issue

#62

Motivation and Context

Fixes a TypeError that breaks this collection.

How Has This Been Tested?

Manually and exhaustively with Postman.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have signed the Adobe Open Source CLA.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.