fix(spdx-reporter): Remove a conflicting license validity check

The `SpdxPackage` constructor already performs a different check with
`Strictness.ALLOW_LICENSEREF_EXCEPTIONS`, see [1]. Remove the check here
to only check once with an aligned strictness. This changes behavior so
that now `LicenseRef`-exceptions are accepted as intended by aa3959e.
Because such exceptions are not part of the SPDX specification, their use
gets logged as warnings, see 4084133.

[1]: https://github.com/oss-review-toolkit/ort/blob/8f00ece/utils/spdx/src/main/kotlin/model/SpdxPackage.kt#L223

Signed-off-by: Sebastian Schuberth <sebastian@doubleopen.org>

plugins/reporters/spdx/src/main/kotlin/Extensions.kt

@@ -181,10 +181,7 @@ internal fun Package.toSpdxPackage(
             licenseInfoResolver.resolveLicenseInfo(id)
                 .filterExcluded()
                 .filter(LicenseView.ONLY_DETECTED)
-                .map { resolvedLicense ->
-                    resolvedLicense.license.takeIf { it.isValid(SpdxExpression.Strictness.ALLOW_DEPRECATED) }
-                        .nullOrBlankToSpdxNoassertionOrNone()
-                }
+                .map { it.license.nullOrBlankToSpdxNoassertionOrNone() }
                 .distinct()
                 .sorted()
         },