KeySpaceUtils.pathToUri inserts extra `/` when path ends with NULL

[ScottDugas]

KeySpaceUtils.pathToUri inserts extra / when path ends with NULL.

I created the following test:

    @Test
    void nullAtEnd() throws RelationalException {
        KeySpace keySpace = new KeySpace(
                createDirectory("null", KeySpaceDirectory.KeyType.NULL, true, null),
                createDirectory("parent", KeySpaceDirectory.KeyType.STRING, true, "parent")
                        .addSubdirectory(createDirectory("null", KeySpaceDirectory.KeyType.NULL, true, null)));
        URI rootUrl = URI.create("/");
        final KeySpacePath rootPath = keySpace.path("null");
        URI url = URI.create("/parent/");
        final KeySpacePath path = keySpace.path("parent").add("null");
        Assertions.assertAll(
                () -> Assertions.assertEquals(rootPath, KeySpaceUtils.toKeySpacePath(rootUrl, keySpace)),
                () -> Assertions.assertEquals(rootUrl, KeySpaceUtils.pathToUri(rootPath)),
                () -> Assertions.assertEquals(path, KeySpaceUtils.toKeySpacePath(url, keySpace)),
                () -> Assertions.assertEquals(url, KeySpaceUtils.pathToUri(path)));
    }

And it fails because the root produces // and the non-root produces /parent//.