Remove required fields for directory templates

When templates were going to be shared between instruments, it made
sense to ensure that they included components that would differentiate
them. Now that each instrument has its own template, this is no longer
useful.

The 'visit' component does not always make sense, eg for test
environments where all data can be written to a central directory.

The fields can still be used if required.

Author: tpoliaw

src/graphql/mod.rs

@@ -1249,8 +1249,6 @@ mod input_template_tests {
 
     #[rstest::rstest]
     #[case::relative("tmp/{instrument}/{visit}")]
-    #[case::missing_instrument("/tmp/{visit}")]
-    #[case::missing_visit("/tmp/{instrument}/data")]
     #[case::invalid_template("/tmp/{nested{placeholder}}")]
     fn invalid_directory_template(#[case] path: String) {
         InputTemplate::<DirectoryTemplate>::parse(Some(Value::String(path))).unwrap_err();

src/paths.rs

@@ -139,7 +139,7 @@ pub struct DetectorTemplate;
 impl PathSpec for DirectoryTemplate {
     type Field = DirectoryField;
 
-    const REQUIRED: &'static [Self::Field] = &[DirectoryField::Instrument, DirectoryField::Visit];
+    const REQUIRED: &'static [Self::Field] = &[];
 
     const ABSOLUTE: bool = true;
     fn describe() -> &'static str {
@@ -221,8 +221,6 @@ mod paths_tests {
 
     #[rstest::rstest]
     #[case::relative("relative/visit/path", InvalidPathTemplate::ShouldBeAbsolute)]
-    #[case::missing_visit("/{instrument}/data", InvalidPathTemplate::MissingField("visit".into()))]
-    #[case::missing_instrument("/data/{visit}", InvalidPathTemplate::MissingField("instrument".into()))]
     #[case::invalid_path_incomplete("/data/{unclosed", TemplateErrorType::Incomplete)]
     #[case::invalid_path_empty("/data/{}", TemplateErrorType::Empty)]
     #[case::invalid_path_nested("/data/{nes{ted}}", TemplateErrorType::Nested)]