hclsyntax: "Arguments" instead of "attributes" in diagnostics
hclsyntax: "Arguments" instead of "attributes" in diagnostics

To reduce confusion with object attributes, we switched a while back to
using the term "argument" to refer to the key/value pairs in a body, but
these diagnostic messages were not updated.

strivecast/hcl,strivecast/hcl,strivecast/hcl,hashicorp/hcl,hashicorp/hcl,hashicorp/hcl,strivecast/hcl,hashicorp/hcl,hashicorp/hcl,strivecast/hcl