[jdk17u-dev] RFR: 8318759: Add four DigiCert root certificates

[Goetz Lindenmaier]

I backport this for parity with 17.0.10-oracle.

As always with these backports I had to adapt the location of the certs and the hash in the test.

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Commit messages:
 - Backport 0ea58048f9b4cdaaa0470b2bcc03913fb3939453

Changes: https://git.openjdk.org/jdk17u-dev/pull/1967/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1967&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8318759
  Stats: 459 lines in 7 files changed: 456 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1967.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1967/head:pull/1967

PR: https://git.openjdk.org/jdk17u-dev/pull/1967