crypto/tls: pretty-print SignatureScheme in tests

[ueno]

When running crypto/tls tests with GOEXPERIMENT=boringcrypto, some
tests are embedded with unreadable hexadecimal values:

=== RUN TestBoringServerSignatureAndHash/5053...3536

This corresponds to a string representation of SignatureScheme as it
implements fmt.Stringer. With this change, the above will be printed
as:

=== RUN TestBoringServerSignatureAndHash/PSSWithSHA256

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Patch Set 1:

(1 comment)

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Patch Set 1:

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Message from Filippo Valsorda:

Patch Set 1: Auto-Submit+1 Code-Review+2 Commit-Queue+1

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Message from Go LUCI:

Patch Set 1:

Dry run: CV is trying the patch.

Bot data: {"action":"start","triggered_at":"2023-09-23T11:12:19Z","revision":"d44b7cfb046ce31230c27a74faeca406d8d9b410"}

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Message from Filippo Valsorda:

Patch Set 1:

(1 comment)

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Message from Filippo Valsorda:

Patch Set 1: -Commit-Queue

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Patch Set 1:

This CL has passed the run

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Patch Set 1: LUCI-TryBot-Result+1

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This PR (HEAD: 19700d5) has been imported to Gerrit for code review.

Please visit Gerrit at https://go-review.googlesource.com/c/go/+/530715.

Important tips:

• Don't comment on this PR. All discussion takes place in Gerrit.
• You need a Gmail or other Google account to register for Gerrit.
• To change your code in response to feedback:
  • Push a new commit to the branch used by your GitHub PR.
  • A new "patch set" will then appear in Gerrit.
  • Respond to each comment by marking as Done in Gerrit if implemented as suggested. You can alternatively write a reply.
  • Critical: you must click the blue Reply button near the top to publish your Gerrit responses.
  • Multiple commits in the PR will be squashed by GerritBot.
• The title and description of the GitHub PR are used to construct the final commit message.
  • Edit these as needed via the GitHub web interface (not via Gerrit or git).
  • You should word wrap the PR description at ~76 characters unless you need longer lines (e.g., for tables or URLs).
• See the Sending a change via GitHub and Reviews sections of the Contribution Guide as well as the FAQ for details.

[gopherbot]

Message from Filippo Valsorda:

Patch Set 3: Auto-Submit+1 Code-Review+2

(1 comment)

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Message from Than McIntosh:

Patch Set 3: Code-Review+1

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[gopherbot]

This PR is being closed because golang.org/cl/530715 has been merged.