Fix Acceptance Tests on Windows

[SBGoods]

Terraform CLI and Provider Versions

N/A

Use Cases or Problem Statement

The acceptance tests for the External provider currently work by building a test program in a set directory relative to the system's GOPATH and validating the outputs of the program against the Terraform configuration. These tests currently fail on Windows operating systems due to the nature of filepaths on Windows compared to UNIX-based systems. This results in errors such as the following:

 data_source_test.go:48: Step 1/1 error: Error running pre-apply refresh: exit status 1
        
        Error: Invalid escape sequence
        
          on terraform_plugin_test.tf line 3, in data "external" "test":
          3:   program = ["C:\Users\runneradmin\go/bin/tf-acc-external-data-source", "cheese"]
        
        The \U escape sequence must be followed by eight hexadecimal digits.

Proposal

We would need to rewrite the buildDataSourceTestProgram() function in data_source_test.go, which builds the file path for the test program, to correctly handle building file paths for Windows systems.

How much impact is this issue causing?

Low

Additional Information

No response

Code of Conduct

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