README: Recommend using EBBR.seq from contrib directory

To avoid issues with the sequence file getting modified in the test report,
recommend using the copy of EBBR.seq that is stored in this repo.

Signed-off-by: Grant Likely <grant.likely@arm.com>

README.md

@@ -17,7 +17,7 @@ command. The parsed report can be found in `result.md`.
 ``` {.sh}
 $ ./parser.py --config EBBR.yaml \
 		</path/to/sct_results/Overall/Summary.ekl> \
-		<path/to/sct_results/Sequence/EBBR.seq>
+		contrib/v21.07_0.9_BETA/EBBR.seq
 INFO apply_rules: Updated 200 test(s) out of 12206 after applying 124 rule(s)
 INFO main: 0 dropped(s), 1 failure(s), 93 ignored(s), 106 known u-boot limitation(s), 12006 pass(s), 0 warning(s)
 ```