Normalize indenting for multi-line descriptions

[anthony-c-martin]

Closes #13982

Microsoft Reviewers: Open in CodeFlow

[github-actions]

Test this change out locally with the following install scripts (Action run 8973333670)

VSCode

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-vsix.sh) --run-id 8973333670

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-vsix.ps1) } -RunId 8973333670"

Azure CLI

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-cli.sh) --run-id 8973333670

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-cli.ps1) } -RunId 8973333670"

[github-actions]

Test Results

    66 files   -     33      66 suites   - 33   22m 0s ⏱️ - 9m 32s
10 883 tests  -     14  10 882 ✅  -     14  1 💤 ±0  0 ❌ ±0 
25 662 runs   - 12 809  25 660 ✅  - 12 808  2 💤  - 1  0 ❌ ±0 

Results for commit eddcedd. ± Comparison against base commit 1c6b9b5.