refactor!: Deprecated OTEL attributes replaced

[dadrus]

Related issue(s)

OTEL has deprecated some of the attributes used so far in exposed metrics/traces. See also HTTP semantic conventions declared stable and Network Deprecated Attributes

• I agree to follow this project's Code of Conduct.
• I have read, and I am following this repository's Contributing Guidelines.
• I have read the Security Policy.
• I have added tests that prove the correctness of my implementation.

Description

This PR updates the code to

• use semconv 1.26.0,
• use client.address instead of the deprecated net.peer.name,
• use client.port instead of the deprecated net.peer.port,
• use server.address instead of the deprecated net.host.name,
• use server.port instead of the deprecated net.host.port,
• use network.peer.address instead of the deprecated net.sock.peer.addr,
• use network.peer.port instead of the deprecated net.sock.peer.port,
• use network.protocol.name and network.protocol.version instead of the deprecated http.flavor,
• use http.request.method instead of the deprecated http.method,
• use url.scheme instead of the deprecated http.scheme.

[codecov]

Codecov Report

Attention: Patch coverage is 90.90909% with 1 line in your changes missing coverage. Please review.

Project coverage is 89.68%. Comparing base (9ade970) to head (6998843).
Report is 1 commits behind head on main.

Files	Patch %	Lines
...handler/middleware/grpc/otelmetrics/interceptor.go	75.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1669      +/-   ##
==========================================
+ Coverage   89.59%   89.68%   +0.08%     
==========================================
  Files         271      271              
  Lines        9006     8993      -13     
==========================================
- Hits         8069     8065       -4     
+ Misses        697      690       -7     
+ Partials      240      238       -2     

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