refactor(ort-utils)!: Remove the fallback to read uncompressed files

Remove the fallback to read uncompressed files from the
`XZCompressedLocalFileStorage`. The fallback was introduced for backward
compatibility with previously uncompressed storage directories, but the
compressed storage is now the default for several years so that the
fallback can be removed.

Signed-off-by: Martin Nonnenmacher <martin.nonnenmacher@bosch.com>

utils/ort/src/funTest/kotlin/storage/XZCompressedLocalFileStorageFunTest.kt

@@ -42,15 +42,4 @@ class XZCompressedLocalFileStorageFunTest : StringSpec({
             content shouldBe "content"
         }
     }
-
-    "Can read existing uncompressed data" {
-        storage { storage, directory ->
-            val file = directory.resolve("existing-file")
-            file.writeText("content")
-
-            val content = storage.read("existing-file").bufferedReader().use(BufferedReader::readText)
-
-            content shouldBe "content"
-        }
-    }
 })

utils/ort/src/main/kotlin/storage/XZCompressedLocalFileStorage.kt

@@ -20,7 +20,6 @@
 package org.ossreviewtoolkit.utils.ort.storage
 
 import java.io.File
-import java.io.FileNotFoundException
 
 import org.apache.commons.compress.compressors.xz.XZCompressorInputStream
 import org.apache.commons.compress.compressors.xz.XZCompressorOutputStream
@@ -36,18 +35,7 @@ class XZCompressedLocalFileStorage(
 ) : LocalFileStorage(directory) {
     override fun transformPath(path: String) = "$path.xz"
 
-    override fun read(path: String) =
-        try {
-            XZCompressorInputStream(super.read(transformPath(path)))
-        } catch (compressedFileNotFoundException: FileNotFoundException) {
-            // Fall back to try reading the uncompressed file.
-            @Suppress("SwallowedException")
-            try {
-                super.read(path)
-            } catch (uncompressedFileNotFoundException: FileNotFoundException) {
-                throw uncompressedFileNotFoundException.initCause(compressedFileNotFoundException)
-            }
-        }
+    override fun read(path: String) = XZCompressorInputStream(super.read(transformPath(path)))
 
     override fun safeOutputStream(path: String) = XZCompressorOutputStream(super.safeOutputStream(transformPath(path)))
 }