fix: Added case handling for loadFromFile() functions that introduc…

…e generated variables in ARM JSON files (#1917)

## Description

- When using a Bicep function like `loadFileAsBase64()` or
`loadFromJson`, the compiled ARM template contains a generated variable
with a name like `$fxv#1` or `$fxv#2`
- This variable currently fails the Pester test 'Variable names should
be camel-cased'
- This PR updates the test by
  - Adding support for the aforementioned deterministic variable name
- Updating the test to return the incorrect variables as opposed to just
claim that there's at least one incorrect variable

## Pipeline Reference

<!-- Insert your Pipeline Status Badge below -->

| Pipeline |
| -------- |
|
[![avm.res.key-vault.vault](https://github.com/AlexanderSehr/bicep-registry-modules/actions/workflows/avm.res.key-vault.vault.yml/badge.svg?branch=users%2Falsehr%2FloadFromJson&event=workflow_dispatch)](https://github.com/AlexanderSehr/bicep-registry-modules/actions/workflows/avm.res.key-vault.vault.yml)
|
|
[![avm.res.storage.storage-account](https://github.com/AlexanderSehr/bicep-registry-modules/actions/workflows/avm.res.storage.storage-account.yml/badge.svg?branch=users%2Falsehr%2FloadFromJson&event=workflow_dispatch)](https://github.com/AlexanderSehr/bicep-registry-modules/actions/workflows/avm.res.storage.storage-account.yml)
(Pester passed) |

## Type of Change

<!-- Use the check-boxes [x] on the options that are relevant. -->

- [x] Update to CI Environment or utlities (Non-module effecting
changes)
- [ ] Azure Verified Module updates:
- [ ] Bugfix containing backwards compatible bug fixes, and I have NOT
bumped the MAJOR or MINOR version in `version.json`:
- [ ] Someone has opened a bug report issue, and I have included "Closes
#{bug_report_issue_number}" in the PR description.
- [ ] The bug was found by the module author, and no one has opened an
issue to report it yet.
- [ ] Feature update backwards compatible feature updates, and I have
bumped the MINOR version in `version.json`.
- [ ] Breaking changes and I have bumped the MAJOR version in
`version.json`.
  - [ ] Update to documentation

---------

Co-authored-by: Erika Gressi <[email protected]>

avm/utilities/pipelines/staticValidation/compliance/module.tests.ps1

@@ -810,17 +810,17 @@ Describe 'Module tests' -Tag 'Module' {
           return
         }
 
-        $CamelCasingFlag = @()
-        $Variable = $templateFileContent.variables.Keys
-
-        foreach ($Variab in $Variable) {
-          if ($Variab.substring(0, 1) -cnotmatch '[a-z]' -or $Variab -match '-') {
-            $CamelCasingFlag += $false
-          } else {
-            $CamelCasingFlag += $true
+        $incorrectVariables = @()
+        $Variables = $templateFileContent.variables.Keys
+
+        foreach ($variable in $Variables) {
+          # ^[a-z]+[a-zA-Z]+$ = starts with lower-case letter & may have uppercase letter later
+          # ^\$fxv#[0-9]+$ = starts with [$fxv#] & ends with a number. This function value is created as a variable when using a Bicep function like loadFileAsBase64() or loadFromJson()
+          if ($variable -cnotmatch '^[a-z]+[a-zA-Z]+$|^\$fxv#[0-9]+$' -or $variable -match '-') {
+            $incorrectVariables += $variable
           }
         }
-        $CamelCasingFlag | Should -Not -Contain $false
+        $incorrectVariables | Should -BeNullOrEmpty
       }
     }