Add linter

[dricross]

Issue #, if available:

Description of changes:

• Upgrade linter to work with our current Go version
  • We were on golangci-lint v1.50. Upgraded to v1.57 to match upstream: https://github.com/open-telemetry/opentelemetry-operator/blob/main/Makefile#L496
• Pin setupenv as latest version doesn't support our current Go version (latest requires 1.23, we're on 1.22)
  • This is to fix running make test locally which was failing for me
• Fix the linting errors that popped up
  • Stole changes to prometheus auth stuff from upstream: open-telemetry/opentelemetry-operator@2910ea9#diff-84d4f444ebfcccd5806c434fcd51a7e1e53a2652ac452472c0750413d095c989R209
• Add linter to github workflow
  • Stole from upstream: https://github.com/open-telemetry/opentelemetry-operator/blob/main/.github/workflows/continuous-integration.yaml#L39C1-L70C21

Here are the errors

/local/home/dricross/workplace/amazon-cloudwatch-agent-operator/bin/golangci-lint run
controllers/common.go:124:20: ineffectual assignment to err (ineffassign)
        desiredObjectMap, err := reconcileDesiredObjectUIDs(ctx, kubeClient, logger, &owner, scheme, desiredObjects...)
                          ^
internal/manifests/collector/suite_test.go:122:6: func `newParams` is unused (unused)
func newParams(taContainerImage string, file string) (manifests.Params, error) {
     ^
internal/manifests/collector/ports.go:73:3: S1011: should replace loop with `ports = append(ports, plist...)` (gosimple)
                for _, p := range plist {
                ^
internal/manifests/collector/ports_test.go:128:2: SA4017: Replace doesn't have side effects and its return value is ignored (staticcheck)
        strings.Replace(cfg, "2800", "2000", 1)
        ^
internal/manifests/collector/ports_test.go:140:2: SA4017: Replace doesn't have side effects and its return value is ignored (staticcheck)
        strings.Replace(cfg, "2900", "2000", 1)
        ^
internal/manifests/collector/ports_test.go:156:2: SA4017: Replace doesn't have side effects and its return value is ignored (staticcheck)
        strings.Replace(cfg, "2900", "2000", 1)
        ^
pkg/instrumentation/podmutator.go:32:2: var `errNoInstancesAvailable` is unused (unused)
        errNoInstancesAvailable      = errors.New("no OpenTelemetry Instrumentation instances available")
        ^
cmd/amazon-cloudwatch-agent-target-allocator/watcher/promOperator.go:289:51: SA1019: endp.BearerTokenSecret is deprecated: use `authorization` instead. (staticcheck)
                if err = store.AddBearerToken(ctx, smNamespace, endp.BearerTokenSecret, objKey); err != nil {
                                                                ^
cmd/amazon-cloudwatch-agent-target-allocator/watcher/promOperator.go:332:52: SA1019: endp.BearerTokenSecret is deprecated: use `authorization` instead. (staticcheck)
                if err = store.AddBearerToken(ctx, pmNamespace, &endp.BearerTokenSecret, objKey); err != nil {
                                                                 ^
integration-tests/manifests/annotations/validate_annotation_methods.go:189:6: S1002: should omit comparison to bool constant, can be simplified to `correct` (gosimple)
                if correct == true {
                   ^
integration-tests/manifests/annotations/validate_annotation_methods.go:203:14: ineffectual assignment to err (ineffassign)
        deployment, err = clientSet.AppsV1().Deployments(amazonCloudwatchNamespace).Get(context.TODO(), amazonControllerManager, metav1.GetOptions{})
                    ^
integration-tests/manifests/annotations/validate_annotation_methods.go:296:3: ineffectual assignment to indexOfAutoAnnotationConfigString (ineffassign)
                indexOfAutoAnnotationConfigString = len(deployment.Spec.Template.Spec.Containers[0].Args) - 1
                ^
integration-tests/manifests/annotations/validate_annotations_namespace_test.go:270:2: ineffectual assignment to startTime (ineffassign)
        startTime := time.Now()
        ^
integration-tests/manifests/annotations/validate_annotations_namespace_test.go:310:2: SA4006: this value of `err` is never used (staticcheck)
        deployment, err := clientSet.AppsV1().Deployments(uniqueNamespace).Get(ctx, deploymentName, metav1.GetOptions{})
        ^
integration-tests/manifests/cmd/validate_instrumentation_vars.go:10:2: SA1019: "io/ioutil" has been deprecated since Go 1.19: As of Go 1.16, the same functionality is now provided by package [io] or package [os], and those implementations should be preferred in new code. See the specific function documentation for details. (staticcheck)
        "io/ioutil"
        ^
make: *** [lint] Error 1

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