Fix computeGitObjectHash() on Linux

* String.length() does not return the expected size

Issue-Ref: 4310
Issue-Url: af3#4310



Signed-off-by: Simon Barner <barner@fortiss.org>

org.fortiss.tooling.ext.quality/src/org/fortiss/tooling/ext/quality/storage/.ratings

-CSVFileWriter.java 0cae6203edc159cec0d3f68c61f4b04a3c61eecd RED
+CSVFileWriter.java 7df3c06231037c5026ca7fa18572d935d444ebf7 RED
 ModelQualityStorageManager.java 8293f17743bdc85e2595eae99b978ed868bd029b RED

org.fortiss.tooling.ext.quality/src/org/fortiss/tooling/ext/quality/storage/CSVFileWriter.java

@@ -233,7 +233,8 @@ public class CSVFileWriter {
 
 			// Construct pre-image (input to hash function) according to Git specification
 			String fileContents = inputBuilder.toString();
-			int n = fileContents.length();
+			// fileContexts.length() does not return the correct length on some platforms (e.g., Linux)
+			int n = fileContents.getBytes().length;
 			String preImage = "blob " + n + "\0" + fileContents;
 
 			// Compute hash and convert it to a hex string