RFR: 8319124: Update XML Security for Java to 3.0.3

[Weijun Wang]

Update XMLDsig implementation to match Apache Santuario 3.0.3.

Changes include (significance in descending order):

- `SignatureMethod.java`: new signature method URIs defined
- `SignatureBaseRSA.java`: `SignatureBaseRSAPSS` and refactoring
- `JCEMapper.java`: use of `ThreadLocal`
- `DigestorOutputStream.java`: one synchronized method
- `XMLUtils.java`: renames, one new method not used anywhere, some log change
- `Init.java`: some refactoring
- `DOMSignatureMethod.java`: new MGF1 methods, some refactoring
- `DOMXMLSignatureFactory.java`: new signature methods
- `santuario.md`, `XMLDSigRI.java`: bump to 3.0.3
- `DOMXMLSignature.java`: some finals
- `NameSpaceSymbTable.java`: renames
- Base64.java: no longer final
- Others: reorder imports, add `@Override`, foreach, diamond operators

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Commit messages:
 - initial change

Changes: https://git.openjdk.org/jdk/pull/16691/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16691&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8319124
  Stats: 1568 lines in 130 files changed: 1150 ins; 231 del; 187 mod
  Patch: https://git.openjdk.org/jdk/pull/16691.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16691/head:pull/16691

PR: https://git.openjdk.org/jdk/pull/16691