Update tests/.gitignore.

.gitignore

@@ -47,8 +47,9 @@
 /tests/compress_generated_random
 /tests/compress_generated_text
 /tests/create_compress_files
+/tests/test_bcj_exact_size
 /tests/test_block_header
 /tests/test_check
 /tests/test_filter_flags
 /tests/test_index
 /tests/test_stream_flags
@@ -50,8 +51,11 @@
 /tests/test_block_header
 /tests/test_check
 /tests/test_filter_flags
 /tests/test_index
 /tests/test_stream_flags
+/tests/xzgrep_test_1.xz
+/tests/xzgrep_test_2.xz
+/tests/xzgrep_test_output
 
 /lib/Makefile
 /tests/Makefile