Update the `ConfigData` import support to allow individual property
sources to be imported with a higher precedence than profile specific
imports.
Prior to this commit, imported sources would always have a higher
precedence than the file that imported them, but a lower precedence
than any profile-specific variant of the same file.
For example, given an `application.properties` that imports `myconfig`,
the contributor tree would be as follows:
ROOT
+- `application.properties`
| +- myconfig
+- `application-<profile>.properties`
The precedence would be:
1) `application-<profile>.properties`
2) myconfig
3) `application.properties`
This works well for most situations, but can be confusing if import is
for a profile-specific property source. For example:
ROOT
+- `application.properties`
| +- myconfig
| +- myconfig-<profile>
+- `application-<profile>.properties`
Results in the order precedence of:
1) `application-<profile>.properties`
2) myconfig-<profile>
3) myconfig
4) `application.properties`
This means that whilst `myconfig` overrides `application.properties`,
`myconfig-profile` does not override `application-<profile>.properties`.
For this specific situation, the preferable order would be:
1) myconfig-<profile>
2) `application-<profile>.properties`
3) myconfig
4) `application.properties`
To support this alternative ordering a new `PROFILE_SPECIFIC` config
data option has been added. Additionally, options may now be specified
on a per-source basis by using the `PropertySourceOptions` interface.
Fixes gh-25766
5774ea3f0c