Support load*Content() functions in UDFs

[anthony-c-martin]

Closes #12912
Also addresses #12698

Microsoft Reviewers: Open in CodeFlow

[github-actions]

Test this change out locally with the following install scripts (Action run 7414869983)

VSCode

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-vsix.sh) --run-id 7414869983

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-vsix.ps1) } -RunId 7414869983"

Azure CLI

• Mac/Linux

  bash <(curl -Ls https://aka.ms/bicep/nightly-cli.sh) --run-id 7414869983

• Windows

  iex "& { $(irm https://aka.ms/bicep/nightly-cli.ps1) } -RunId 7414869983"

[github-actions]

Test Results

    88 files   -    11      88 suites   - 11   34m 14s ⏱️ - 22m 12s
10 471 tests  -    13  10 469 ✅  -    14  0 💤 ±0  2 ❌ +1 
31 229 runs   - 6 919  31 224 ✅  - 6 923  0 💤 ±0  5 ❌ +4 

For more details on these failures, see this check.

Results for commit 42da978. ± Comparison against base commit 6dfa50e.

♻️ This comment has been updated with latest results.

[matwilko]

@anthony-c-martin From issue to merged PR in 3 hours? Kudos, that's some impressive velocity! 💯