JCE: fix threaded digest tests hanging on FIPS error

Add latch.countDown() and return in catch block to prevent
thread from falling through to null MessageDigest reference.

Author: cconlon

src/test/java/com/wolfssl/provider/jce/test/WolfCryptMessageDigestMd5Test.java

@@ -323,6 +323,8 @@ public void testMd5Threaded()
                              NoSuchProviderException e) {
                         /* add empty array on failure, will error out below */
                         results.add(new byte[] {0});
+                        latch.countDown();
+                        return;
                     }
 
                     /* process/update in 1024-byte chunks */

src/test/java/com/wolfssl/provider/jce/test/WolfCryptMessageDigestSha256Test.java

@@ -312,6 +312,8 @@ public void testSha256Threaded()
                              NoSuchProviderException e) {
                         /* add empty array on failure, will error out below */
                         results.add(new byte[] {0});
+                        latch.countDown();
+                        return;
                     }
 
                     /* process/update in 1024-byte chunks */

src/test/java/com/wolfssl/provider/jce/test/WolfCryptMessageDigestSha384Test.java

@@ -335,6 +335,8 @@ public void testSha384Threaded()
                              NoSuchProviderException e) {
                         /* add empty array on failure, will error out below */
                         results.add(new byte[] {0});
+                        latch.countDown();
+                        return;
                     }
 
                     /* process/update in 1024-byte chunks */

src/test/java/com/wolfssl/provider/jce/test/WolfCryptMessageDigestSha3Test.java

@@ -345,6 +345,8 @@ public void testSha3Threaded()
                              NoSuchProviderException e) {
                         /* Add empty array on failure, will error out below */
                         results.add(new byte[] {0});
+                        latch.countDown();
+                        return;
                     }
 
                     /* Process/update in 1024-byte chunks */

src/test/java/com/wolfssl/provider/jce/test/WolfCryptMessageDigestSha512Test.java

@@ -355,6 +355,8 @@ public void testSha512Threaded()
                              NoSuchProviderException e) {
                         /* add empty array on failure, will error out below */
                         results.add(new byte[] {0});
+                        latch.countDown();
+                        return;
                     }
 
                     /* process/update in 1024-byte chunks */

src/test/java/com/wolfssl/provider/jce/test/WolfCryptMessageDigestShaTest.java

@@ -331,6 +331,8 @@ public void testShaThreaded()
                              NoSuchProviderException e) {
                         /* add empty array on failure, will error out below */
                         results.add(new byte[] {0});
+                        latch.countDown();
+                        return;
                     }
 
                     /* process/update in 1024-byte chunks */