Fix //third_party tests with $(rootpath)

Fixes `{strict_deps,unused_dependency_checker}_test` from
`//third_party/dependency_analyzer/src/test` under Bazel 8 by updating
`$(location)` to `$(rootpath)`. Part of bazelbuild#1652.

`//third_party/dependency_analyzer/src/test:strict_deps_test` and
`//third_party/dependency_analyzer/src/test:unused_dependency_checker_test`
both failed with errors of the form:

```txt
StrictDepsTest:
- error on indirect dependency target *** FAILED *** (379 milliseconds)
  nice errors on sequence of strings.this.infos.exists(nice errors on
  sequence of strings.this.checkErrorContainsMessage(target)) was false
  expected an error on //commons:Target to appear in errors (with
  buildozer command)!
  Errors: List(object apache is not a member of package org)
  (StrictDepsTest.scala:85)
```

This happened both under `WORKSPACE` and Bzlmod.

third_party/dependency_analyzer/src/test/analyzer_test.bzl

@@ -61,7 +61,7 @@ def tests():
         ],
         jvm_flags = common_jvm_flags + [
             "-Dguava.jar.location=$(rootpath @com_google_guava_guava_21_0_with_file//jar)",
-            "-Dapache.commons.jar.location=$(location @org_apache_commons_commons_lang_3_5_without_file//:linkable_org_apache_commons_commons_lang_3_5_without_file)",
+            "-Dapache.commons.jar.location=$(rootpath @org_apache_commons_commons_lang_3_5_without_file//:linkable_org_apache_commons_commons_lang_3_5_without_file)",
         ],
         unused_dependency_checker_mode = "off",
         deps = scala_std_dependencies + [
@@ -80,7 +80,7 @@ def tests():
             "io/bazel/rulesscala/dependencyanalyzer/UnusedDependencyCheckerTest.scala",
         ],
         jvm_flags = common_jvm_flags + [
-            "-Dapache.commons.jar.location=$(location @org_apache_commons_commons_lang_3_5_without_file//:linkable_org_apache_commons_commons_lang_3_5_without_file)",
+            "-Dapache.commons.jar.location=$(rootpath @org_apache_commons_commons_lang_3_5_without_file//:linkable_org_apache_commons_commons_lang_3_5_without_file)",
         ],
         unused_dependency_checker_mode = "off",
         deps = scala_std_dependencies + [