server: add more context to panic message

[cenkalti]

Adding more context to the panic log message for #14211 .

Our goal is to capture enough information that will allow us to reproduce the issue when it happens again.

[codecov-commenter]

Codecov Report

Merging #14667 (580a86e) into main (5073af6) will decrease coverage by 0.21%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main   #14667      +/-   ##
==========================================
- Coverage   75.75%   75.53%   -0.22%     
==========================================
  Files         457      457              
  Lines       37292    37299       +7     
==========================================
- Hits        28249    28174      -75     
- Misses       7287     7359      +72     
- Partials     1756     1766      +10     

Flag	Coverage Δ
all	75.53% <0.00%> (-0.22%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
server/storage/mvcc/kvstore_txn.go	76.19% <0.00%> (-2.94%)	⬇️
client/pkg/v3/tlsutil/tlsutil.go	83.33% <0.00%> (-8.34%)	⬇️
client/pkg/v3/testutil/leak.go	62.83% <0.00%> (-7.08%)	⬇️
client/v3/leasing/util.go	91.66% <0.00%> (-6.67%)	⬇️
server/etcdserver/api/v3rpc/interceptor.go	76.56% <0.00%> (-6.25%)	⬇️
client/v3/namespace/watch.go	87.87% <0.00%> (-6.07%)	⬇️
server/storage/mvcc/watchable_store.go	85.50% <0.00%> (-5.08%)	⬇️
client/v3/concurrency/session.go	88.63% <0.00%> (-4.55%)	⬇️
server/proxy/grpcproxy/watch.go	92.48% <0.00%> (-4.05%)	⬇️
server/etcdserver/txn/util.go	75.47% <0.00%> (-3.78%)	⬇️
... and 19 more

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[ahrtr]

LGTM

[cenkalti]

@ahrtr Thanks for quick approval. Can I backport it to the 3.4 and 3.5 releases?

[ahrtr]

@ahrtr Thanks for quick approval. Can I backport it to the 3.4 and 3.5 releases?

Sure.