[chore]: Bump github.com/prometheus/client_golang from 1.20.0 to 1.20.2 (#3239)

Bumps [github.com/prometheus/client_golang](https://github.com/prometheus/client_golang) from 1.20.0 to 1.20.2.
- [Release notes](https://github.com/prometheus/client_golang/releases)
- [Changelog](https://github.com/prometheus/client_golang/blob/main/CHANGELOG.md)
- [Commits](https://github.com/prometheus/client_golang/compare/v1.20.0...v1.20.2)

---
updated-dependencies:
- dependency-name: github.com/prometheus/client_golang
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

vendor/github.com/prometheus/client_golang/prometheus/process_collector.go

@@ -140,6 +140,8 @@ func (c *processCollector) Describe(ch chan<- *Desc) {
 	ch <- c.maxVsize
 	ch <- c.rss
 	ch <- c.startTime
+	ch <- c.inBytes
+	ch <- c.outBytes
 }
 
 // Collect returns the current state of all metrics of the collector.

vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go

@@ -203,8 +203,10 @@ func HandlerForTransactional(reg prometheus.TransactionalGatherer, opts HandlerO
 
 		defer closeWriter()
 
-		rsp.Header().Set(contentEncodingHeader, encodingHeader)
-
+		// Set Content-Encoding only when data is compressed
+		if encodingHeader != string(Identity) {
+			rsp.Header().Set(contentEncodingHeader, encodingHeader)
+		}
 		enc := expfmt.NewEncoder(w, contentType)
 
 		// handleError handles the error according to opts.ErrorHandling