airframe-grpc: Fix syntax for Scala 3

[xerial]

• Fix for Scala 3 syntax

TODO in another PR

• Router needs to register a trait factory in Router macros
  • Prepare a trait instantiation factory. Related to Add reflect ClassDef.apply and Symbol.newClass scala/scala3#14124 Quotes: generate arbitrary trait or class implementations scala/scala3#11685
• Fix Alias support in Surface. Related to https://twitter.com/exoego/status/1523469845676711936 (@exoego )

[codecov]

Codecov Report

Merging #2193 (51a8d69) into master (1b94fa6) will decrease coverage by 0.00%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #2193      +/-   ##
==========================================
- Coverage   82.57%   82.57%   -0.01%     
==========================================
  Files         312      312              
  Lines       12352    12353       +1     
  Branches      790      790              
==========================================
  Hits        10200    10200              
- Misses       2152     2153       +1     

Impacted Files	Coverage Δ
...in/scala/wvlet/airframe/http/grpc/GrpcServer.scala	63.33% <0.00%> (-2.19%)	⬇️

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[xerial]

Filed follow-up tasks in #2194

[xerial]

This PR only fixes Scala 3 incompatible syntaxes