Improve the config.js related inconsistencies

[yomalip]

Description

related to https://github.com/wso2-enterprise/choreo/issues/36393

This pull request updates documentation across multiple files to standardize the path used for referencing the config.js file and clarify instructions regarding its usage. The changes ensure consistency and improve the accuracy of the documentation.

Standardization of config.js path references:

• en/developer-docs/docs/develop-components/develop-web-applications/build-and-deploy-a-single-page-web-application.md: Updated the script tag to use ./public/config.js instead of %PUBLIC_URL%/config.js.
• en/developer-docs/docs/develop-components/sharing-and-reusing/use-a-connection-in-your-web-application.md: Replaced /public/config.js with ./public/config.js in two instances to ensure consistent path usage. [1] [2]

Clarification of instructions regarding config.js:

• en/developer-docs/docs/quick-start-guides/deploy-a-web-application-that-consumes-a-backend-service.md: Changed a tip to a note, emphasizing the mandatory usage of ./public/config.js for referring to the configuration file.
• en/developer-docs/docs/tutorials/consume-an-api-hosted-in-choreo.md: Updated a tip to a note to clearly state the requirement to use ./public/config.js for referencing the mounted configuration file.

Type of change

• Change is only applicable for Developer view
• Change is only applicable for Platform Engineer view
• Change is applicable for both Developer and Platform Engineer views

Testing

• Change is tested in Developer view
• Change is tested in Platform Engineer view

Related issues

List related issues here