Fix typos in FormatExceptionPolicyStrict (#215)

Fix typos in JavaDoc of method `excludePath(String)`.

Author: thc202

lib/src/main/java/com/diffplug/spotless/FormatExceptionPolicyStrict.java

@@ -34,7 +34,7 @@ public void excludeStep(String stepName) {
 		excludeSteps.add(Objects.requireNonNull(stepName));
 	}
 
-	/** Adds a realtive pathx to exclude. */
+	/** Adds a relative path to exclude. */
 	public void excludePath(String relativePath) {
 		excludePaths.add(Objects.requireNonNull(relativePath));
 	}