Ensure \n is used when emitting template

[shenglol]

Currently, Bicep generates inconsistent newlines depending on whether the template is built using the Build command (and with or without the --stdout flag) or through the VS Code extension.

This PR updates the emission code to consistently use \n for newlines. This change should prevent issues like #14383 in the future.

Microsoft Reviewers: Open in CodeFlow

[github-actions]

Test this change out locally with the following install scripts (Action run 9982991637)

VSCode

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-vsix.sh) --run-id 9982991637

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-vsix.ps1) } -RunId 9982991637"

Azure CLI

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-cli.sh) --run-id 9982991637

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-cli.ps1) } -RunId 9982991637"

[github-actions]

Dotnet Test Results

    72 files   -     36      72 suites   - 36   23m 27s ⏱️ - 10m 2s
10 955 tests  -     20  10 955 ✅  -     19  0 💤 ±0  0 ❌  - 1 
25 806 runs   - 12 899  25 806 ✅  - 12 898  0 💤 ±0  0 ❌  - 1 

Results for commit 0e2f891. ± Comparison against base commit 00a5bc4.