Fix missing reaction on command parsing exception

[Copilot]

When check_test_cmd_mu2e() raises a general exception (not ValueError), the bot silently fails without providing user feedback via GitHub reaction.

Changes

• Set reaction_t = "confused" in general exception handler (line 409)

This aligns with existing behavior:

• Line 406: "-1" reaction for ValueError (invalid inputs)
• Line 436: "confused" reaction when test already triggered
• Line 456: "confused" reaction when bot mentioned but no valid command

except Exception:
    log.exception("Failed to trigger a test.")
    reaction_t = "confused"  # Now provides feedback to user

Before: reaction_t remains None, line 459 skips reaction creation
After: Users get confused emoji (😕) indicating bot saw comment but couldn't process it

Original prompt

search the code for a place where it might return a white or no-color smilie face to indicate that no actions was taken

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[rlcee]

@copilot I looked at the output page source code and I see:

and
class="octicon octicon-smiley social-button-emoji">
this might be the white smiley face I was referring to

[Copilot]

@copilot I looked at the output page source code and I see:

and...

Could you please complete your comment? It looks like it was cut off after "I see:". What did you find in the output page source code?

[rlcee]

@copilot The text included html formatting, please parse with that in mind. I repeat it below

and class="octicon octicon-smiley social-button-emoji"> this might be the white smiley face I was referring to

[Copilot]

@copilot The text included html formatting, please parse with that in mind. I repeat it below

...

I don't see the content you mentioned repeating below. Could you please share what you found in the output page source code? You can paste it as a code block or attach it as a file if the HTML formatting is being stripped.