feat: Add ReservedIpIds to the NLB spec

[joekr]

API guidelines
https://docs.oracle.com/en-us/iaas/api/#/en/networkloadbalancer/20200501/datatypes/CreateNetworkLoadBalancerDetails

What this PR does / why we need it:
Adds support so nlbSpec can set reservedIpIds. This allows a reserved IP address to be set on the Network Load Balancer.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #470

[joekr]

unit tests

        github.com/oracle/cluster-api-provider-oci              coverage: 0.0% of statements
ok      github.com/oracle/cluster-api-provider-oci/api/v1beta1  28.976s coverage: 23.3% of statements
ok      github.com/oracle/cluster-api-provider-oci/api/v1beta2  2.222s  coverage: 18.0% of statements
ok      github.com/oracle/cluster-api-provider-oci/cloud/config 1.543s  coverage: 86.1% of statements
        github.com/oracle/cluster-api-provider-oci/cloud/metrics                coverage: 0.0% of statements
ok      github.com/oracle/cluster-api-provider-oci/cloud/ociutil        0.653s  coverage: 15.9% of statements
ok      github.com/oracle/cluster-api-provider-oci/cloud/ociutil/ptr    1.089s  coverage: 100.0% of statements
ok      github.com/oracle/cluster-api-provider-oci/cloud/scope  21.073s coverage: 74.5% of statements
        github.com/oracle/cluster-api-provider-oci/cloud/scope/mocks            coverage: 0.0% of statements
        github.com/oracle/cluster-api-provider-oci/cloud/services/base          coverage: 0.0% of statements
        github.com/oracle/cluster-api-provider-oci/cloud/services/base/mock_base                coverage: 0.0% of statements
?       github.com/oracle/cluster-api-provider-oci/cloud/services/compute       [no test files]
        github.com/oracle/cluster-api-provider-oci/cloud/services/compute/mock_compute          coverage: 0.0% of statements
?       github.com/oracle/cluster-api-provider-oci/cloud/services/computemanagement     [no test files]
        github.com/oracle/cluster-api-provider-oci/cloud/services/computemanagement/mock_computemanagement              coverage: 0.0% of statements
?       github.com/oracle/cluster-api-provider-oci/cloud/services/containerengine       [no test files]
        github.com/oracle/cluster-api-provider-oci/cloud/services/containerengine/mock_containerengine          coverage: 0.0% of statements
?       github.com/oracle/cluster-api-provider-oci/cloud/services/identity      [no test files]
        github.com/oracle/cluster-api-provider-oci/cloud/services/identity/mock_identity                coverage: 0.0% of statements
?       github.com/oracle/cluster-api-provider-oci/cloud/services/loadbalancer  [no test files]
        github.com/oracle/cluster-api-provider-oci/cloud/services/loadbalancer/mock_lb          coverage: 0.0% of statements
?       github.com/oracle/cluster-api-provider-oci/cloud/services/networkloadbalancer   [no test files]
        github.com/oracle/cluster-api-provider-oci/cloud/services/networkloadbalancer/mock_nlb          coverage: 0.0% of statements
?       github.com/oracle/cluster-api-provider-oci/cloud/services/vcn   [no test files]
        github.com/oracle/cluster-api-provider-oci/cloud/services/vcn/mock_vcn          coverage: 0.0% of statements
?       github.com/oracle/cluster-api-provider-oci/cloud/services/workrequests  [no test files]
        github.com/oracle/cluster-api-provider-oci/cloud/services/workrequests/mock_workrequests                coverage: 0.0% of statements
ok      github.com/oracle/cluster-api-provider-oci/cloud/util   1.307s  coverage: 60.9% of statements
ok      github.com/oracle/cluster-api-provider-oci/controllers  3.112s  coverage: 59.2% of statements
ok      github.com/oracle/cluster-api-provider-oci/exp/api/v1beta1      8.159s  coverage: 15.3% of statements
ok      github.com/oracle/cluster-api-provider-oci/exp/api/v1beta2      1.361s  coverage: 5.8% of statements
ok      github.com/oracle/cluster-api-provider-oci/exp/controllers      2.697s  coverage: 56.3% of statements
        github.com/oracle/cluster-api-provider-oci/feature              coverage: 0.0% of statements
?       github.com/oracle/cluster-api-provider-oci/version      [no test files]

e2e tests

Summarizing 1 Failure:
  [FAIL] Workload cluster creation [It] Cloud Provider OCI testing [PRBlocking]
  /home/ubuntu/go/pkg/mod/sigs.k8s.io/cluster-api/test@v1.10.6/framework/controlplane_helpers.go:153

Ran 9 of 31 Specs in 4295.515 seconds
FAIL! -- 8 Passed | 1 Failed | 0 Pending | 22 Skipped

Then I ran the one that failed and it passed.

GINKGO_FOCUS="Cloud Provider OCI testing" scripts/ci-e2e.sh
...
...
...
Ran 1 of 31 Specs in 999.392 seconds
SUCCESS! -- 1 Passed | 0 Failed | 0 Pending | 30 Skipped