RFR: 7903061: Don't upload build artifact

[Christian Stein]

This commit removes the step that uploads a build artifact as part of the test workflow.

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Commit messages:
 - Don't upload build artifact

Changes: https://git.openjdk.java.net/jtreg/pull/42/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jtreg&pr=42&range=00
  Issue: https://bugs.openjdk.java.net/browse/CODETOOLS-7903061
  Stats: 8 lines in 1 file changed: 0 ins; 8 del; 0 mod
  Patch: https://git.openjdk.java.net/jtreg/pull/42.diff
  Fetch: git fetch https://git.openjdk.java.net/jtreg pull/42/head:pull/42

PR: https://git.openjdk.java.net/jtreg/pull/42