docs: Update build.sh to indicate usage of multiple profiles

[aseques]

Clarify the usage of multiple profiles

Description

Clarify in the build script the usage of multiple profiles (mentioned here)

Please check if the PR fulfills these requirements

• The commit message follows our guidelines: https://docs.mapstore.geosolutionsgroup.com/en/latest/developer-guide/printing-module/#building-from-the-source
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (check one with "x", remove the others)

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

Simple documentation clarification

Issue

What is the current behavior?

The usage of commas to use multiple profiles is in the docs but a bit difficult to find

What is the new behavior?
Usage explained within the code

Breaking change

Does this PR introduce a breaking change? (check one with "x", remove the other)

• Yes, and I documented them in migration notes
• No

Other useful information

[offtherailz]

Thank you for contributing @aseques ❤️ 🚀