Should enum inputs be case-insensitive?

[anthony-c-martin]

We have various action inputs that take a fixed set of values, or a list of a fixed set of values.

Some examples:
type - must be either deployment or deploymentStacks
scope - must be either tenant, managementGroup, subscription or resourceGroup

Currently our validation logic is strict - the casing has to match exactly. This means that we would reject scope: Tenant or type: deploymentstacks.

As raised in #85 (comment), this is a bit odd with our environment input, as it requires camel case (azureCloud, azureChinaCloud, azureGermanCloud, azureUSGovernment), whereas the environment input for the "azure-login" action (which this is commonly used with) requires Pascal Case (AzureCloud, AzureChinaCloud, AzureGermanCloud, AzureUSGovernment) - see https://github.com/marketplace/actions/azure-login#environment

IMO the best option for dealing with this inconsistency would be to relax our validation such that we don't care about casing for enum inputs.