func (s *ProjectMirrorService) EditProjectMirror(pid interface{}, mirror int, opt *EditProjectMirrorOptions, options ...RequestOptionFunc) (*ProjectMirror, *Response, error) {
	project, err := parseID(pid)
	if err != nil {
		return nil, nil, err
	}
	u := fmt.Sprintf("projects/%s/remote_mirrors/%d", pathEscape(project), mirror)
	req, err := s.client.NewRequest(http.MethodPut, u, opt, options)
	if err != nil {
		return nil, nil, err
	}
	pm := new(ProjectMirror)
	resp, err := s.client.Do(req, pm)
	if err != nil {
		return nil, resp, err
	}
	return pm, resp, err
}
EditProjectMirror updates a project team member to a specified access level..

GitLab API docs:
https://docs.gitlab.com/ce/api/remote_mirrors.html#update-a-remote-mirrors-attributes
package gitlab
import (
	"fmt"
	"net/http"
	"time"
)
type ProjectMirrorService struct {
	client *Client
}
type ProjectMirror struct {
	Enabled                bool       `json:"enabled"`
	ID                     int        `json:"id"`
	LastError              string     `json:"last_error"`
	LastSuccessfulUpdateAt *time.Time `json:"last_successful_update_at"`
	LastUpdateAt           *time.Time `json:"last_update_at"`
	LastUpdateStartedAt    *time.Time `json:"last_update_started_at"`
	OnlyProtectedBranches  bool       `json:"only_protected_branches"`
	KeepDivergentRefs      bool       `json:"keep_divergent_refs"`
	UpdateStatus           string     `json:"update_status"`
	URL                    string     `json:"url"`
}
type ListProjectMirrorOptions ListOptions
func (s *ProjectMirrorService) ListProjectMirror(pid interface{}, opt *ListProjectMirrorOptions, options ...RequestOptionFunc) ([]*ProjectMirror, *Response, error) {
	project, err := parseID(pid)
	if err != nil {
		return nil, nil, err
	}
	u := fmt.Sprintf("projects/%s/remote_mirrors", pathEscape(project))
	req, err := s.client.NewRequest(http.MethodGet, u, opt, options)
	if err != nil {
		return nil, nil, err
	}
	var pm []*ProjectMirror
	resp, err := s.client.Do(req, &pm)
	if err != nil {
		return nil, resp, err
	}
	return pm, resp, err
}
type AddProjectMirrorOptions struct {
	URL                   *string `url:"url,omitempty" json:"url,omitempty"`
	Enabled               *bool   `url:"enabled,omitempty" json:"enabled,omitempty"`
	OnlyProtectedBranches *bool   `url:"only_protected_branches,omitempty" json:"only_protected_branches,omitempty"`
	KeepDivergentRefs     *bool   `url:"keep_divergent_refs,omitempty" json:"keep_divergent_refs,omitempty"`
}
func (s *ProjectMirrorService) AddProjectMirror(pid interface{}, opt *AddProjectMirrorOptions, options ...RequestOptionFunc) (*ProjectMirror, *Response, error) {
	project, err := parseID(pid)
	if err != nil {
		return nil, nil, err
	}
	u := fmt.Sprintf("projects/%s/remote_mirrors", pathEscape(project))
	req, err := s.client.NewRequest(http.MethodPost, u, opt, options)
	if err != nil {
		return nil, nil, err
	}
	pm := new(ProjectMirror)
	resp, err := s.client.Do(req, pm)
	if err != nil {
		return nil, resp, err
	}
	return pm, resp, err
}
type EditProjectMirrorOptions struct {
	Enabled               *bool `url:"enabled,omitempty" json:"enabled,omitempty"`
	OnlyProtectedBranches *bool `url:"only_protected_branches,omitempty" json:"only_protected_branches,omitempty"`
	KeepDivergentRefs     *bool `url:"keep_divergent_refs,omitempty" json:"keep_divergent_refs,omitempty"`
}