Enable Lint Rule: modifies-value-receiver (#5517)

## Which problem is this PR solving?
-  Partial Fix for #5506

## Description of the changes
- Enabled modifies-value-receiver in revive linter. 
- Removed instances where pass-by-values where re-assigned and returned.

## How was this change tested?
- `make lint` `make test`

## Checklist
- [x] I have read
https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
- [x] I have signed all commits
- [ ] I have added unit tests for the new functionality
- [x] I have run lint and test steps successfully
  - for `jaeger`: `make lint test`
  - for `jaeger-ui`: `yarn lint` and `yarn test`

---------

Signed-off-by: FlamingSaint <[email protected]>

.golangci.yml

@@ -186,9 +186,6 @@ linters-settings:
         # TBD - often triggered in tests
         - name: unhandled-error
           disabled: true
-        # this one looks like it's catching real errors, need to enable it
-        - name: modifies-value-receiver
-          disabled: true
         # often looks like a red herring, needs investigation
         - name: flag-parameter
           disabled: true

cmd/agent/app/builder.go

@@ -167,10 +167,11 @@ func (b *Builder) getProcessors(rep reporter.Reporter, mFactory metrics.Factory,
 
 // GetHTTPServer creates an HTTP server that provides sampling strategies and baggage restrictions to client libraries.
 func (c HTTPServerConfiguration) getHTTPServer(manager configmanager.ClientConfigManager, mFactory metrics.Factory, logger *zap.Logger) *http.Server {
-	if c.HostPort == "" {
-		c.HostPort = defaultHTTPServerHostPort
+	hostPort := c.HostPort
+	if hostPort == "" {
+		hostPort = defaultHTTPServerHostPort
 	}
-	return httpserver.NewHTTPServer(c.HostPort, manager, mFactory, logger)
+	return httpserver.NewHTTPServer(hostPort, manager, mFactory, logger)
 }
 
 // GetThriftProcessor gets a TBufferedServer backed Processor using the collector configuration

model/dependencies.go

@@ -22,8 +22,9 @@ const (
 
 // ApplyDefaults applies defaults to the DependencyLink.
 func (d DependencyLink) ApplyDefaults() DependencyLink {
-	if d.Source == "" {
-		d.Source = JaegerDependencyLinkSource
+	dd := d
+	if dd.Source == "" {
+		dd.Source = JaegerDependencyLinkSource
 	}
-	return d
+	return dd
 }