Set IsSensitive in variable schema

[beandrad]

So that terraform-ls can return information about whether a variable
value is sensitive.

[radeksimko]

Thank you for the PR!

Can you also reflect the sensitivity flag in the provider schema, please?

terraform-schema/schema/convert_json.go

Lines 106 to 113 in 2fb6ae2

	cAttrs[name] = &schema.AttributeSchema{
	Description: markupContent(attr.Description, attr.DescriptionKind),
	IsDeprecated: attr.Deprecated,
	IsComputed: attr.Computed,
	IsOptional: attr.Optional,
	IsRequired: attr.Required,
	Expr: exprConstraintsFromAttribute(attr),
	}

[beandrad]

That was fun :D

[radeksimko]

LGTM, thank you!