Remove replace directives and use own fork to make go get work again (#1028)

See https://github.com/golang/go/issues/30354
go get doesn't honor the go.mod replace options.

vendor/github.com/yaegashi/msgraph.go/msauth/msauth.go

@@ -1,148 +0,0 @@
-// Package msauth implements a library to authorize against Microsoft identity platform:
-// https://docs.microsoft.com/en-us/azure/active-directory/develop/
-//
-// It utilizes v2.0 endpoint
-// so it can authorize users with both personal (Microsoft) and organizational (Azure AD) account.
-package msauth
-
-import (
-	"context"
-	"encoding/json"
-	"errors"
-	"fmt"
-	"io/ioutil"
-	"net/http"
-	"net/url"
-	"sync"
-	"time"
-
-	"golang.org/x/oauth2"
-)
-
-const (
-	// DefaultMSGraphScope is the default scope for MS Graph API
-	DefaultMSGraphScope = "https://graph.microsoft.com/.default"
-	endpointURLFormat   = "https://login.microsoftonline.com/%s/oauth2/v2.0/%s"
-)
-
-// TokenError is returned on failed authentication
-type TokenError struct {
-	ErrorObject      string `json:"error"`
-	ErrorDescription string `json:"error_description"`
-}
-
-// Error implements error interface
-func (t *TokenError) Error() string {
-	return fmt.Sprintf("%s: %s", t.ErrorObject, t.ErrorDescription)
-}
-
-func generateKey(tenantID, clientID string) string {
-	return fmt.Sprintf("%s:%s", tenantID, clientID)
-}
-
-func deviceCodeURL(tenantID string) string {
-	return fmt.Sprintf(endpointURLFormat, tenantID, "devicecode")
-}
-
-func tokenURL(tenantID string) string {
-	return fmt.Sprintf(endpointURLFormat, tenantID, "token")
-}
-
-type tokenJSON struct {
-	AccessToken  string `json:"access_token"`
-	TokenType    string `json:"token_type"`
-	RefreshToken string `json:"refresh_token"`
-	ExpiresIn    int    `json:"expires_in"`
-}
-
-func (e *tokenJSON) expiry() (t time.Time) {
-	if v := e.ExpiresIn; v != 0 {
-		return time.Now().Add(time.Duration(v) * time.Second)
-	}
-	return
-}
-
-// Manager is oauth2 token cache manager
-type Manager struct {
-	mu         sync.Mutex
-	TokenCache map[string]*oauth2.Token
-}
-
-// NewManager returns a new Manager instance
-func NewManager() *Manager {
-	return &Manager{TokenCache: map[string]*oauth2.Token{}}
-}
-
-// LoadBytes loads token cache from opaque bytes (it's actually JSON)
-func (m *Manager) LoadBytes(b []byte) error {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	return json.Unmarshal(b, &m.TokenCache)
-}
-
-// SaveBytes saves token cache to opaque bytes (it's actually JSON)
-func (m *Manager) SaveBytes() ([]byte, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	return json.Marshal(m.TokenCache)
-}
-
-// LoadFile loads token cache from file
-func (m *Manager) LoadFile(path string) error {
-	b, err := ioutil.ReadFile(path)
-	if err != nil {
-		return err
-	}
-	return m.LoadBytes(b)
-}
-
-// SaveFile saves token cache to file
-func (m *Manager) SaveFile(path string) error {
-	b, err := m.SaveBytes()
-	if err != nil {
-		return err
-	}
-	return ioutil.WriteFile(path, b, 0644)
-}
-
-// Cache stores a token into token cache
-func (m *Manager) Cache(tenantID, clientID string, token *oauth2.Token) {
-	m.TokenCache[generateKey(tenantID, clientID)] = token
-}
-
-// requestToken requests a token from the token endpoint
-// TODO(ctx): use http client from ctx
-func (m *Manager) requestToken(ctx context.Context, tenantID, clientID string, values url.Values) (*oauth2.Token, error) {
-	res, err := http.PostForm(tokenURL(tenantID), values)
-	if err != nil {
-		return nil, err
-	}
-	defer res.Body.Close()
-	b, err := ioutil.ReadAll(res.Body)
-	if err != nil {
-		return nil, err
-	}
-	if res.StatusCode != http.StatusOK {
-		var terr *TokenError
-		err = json.Unmarshal(b, &terr)
-		if err != nil {
-			return nil, err
-		}
-		return nil, terr
-	}
-	var tj *tokenJSON
-	err = json.Unmarshal(b, &tj)
-	if err != nil {
-		return nil, err
-	}
-	token := &oauth2.Token{
-		AccessToken:  tj.AccessToken,
-		TokenType:    tj.TokenType,
-		RefreshToken: tj.RefreshToken,
-		Expiry:       tj.expiry(),
-	}
-	if token.AccessToken == "" {
-		return nil, errors.New("msauth: server response missing access_token")
-	}
-	return token, nil
-}