chore(goconsts): use proper constants for http methods

Signed-off-by: Jan Larwig <jan@larwig.com>

providers/azure.go

@@ -166,7 +166,7 @@ func (p *AzureProvider) Redeem(ctx context.Context, redirectURL, code, codeVerif
 
 	err = requests.New(p.RedeemURL.String()).
 		WithContext(ctx).
-		WithMethod("POST").
+		WithMethod(http.MethodPost).
 		WithBody(bytes.NewBufferString(params.Encode())).
 		SetHeader("Content-Type", "application/x-www-form-urlencoded").
 		Do().
@@ -334,7 +334,7 @@ func (p *AzureProvider) redeemRefreshToken(ctx context.Context, s *sessions.Sess
 
 	err = requests.New(p.RedeemURL.String()).
 		WithContext(ctx).
-		WithMethod("POST").
+		WithMethod(http.MethodPost).
 		WithBody(bytes.NewBufferString(params.Encode())).
 		SetHeader("Content-Type", "application/x-www-form-urlencoded").
 		Do().

providers/google.go

@@ -219,7 +219,7 @@ func (p *GoogleProvider) Redeem(ctx context.Context, redirectURL, code, codeVeri
 
 	err = requests.New(p.RedeemURL.String()).
 		WithContext(ctx).
-		WithMethod("POST").
+		WithMethod(http.MethodPost).
 		WithBody(bytes.NewBufferString(params.Encode())).
 		SetHeader("Content-Type", "application/x-www-form-urlencoded").
 		Do().
@@ -543,7 +543,7 @@ func (p *GoogleProvider) redeemRefreshToken(ctx context.Context, s *sessions.Ses
 
 	err = requests.New(p.RedeemURL.String()).
 		WithContext(ctx).
-		WithMethod("POST").
+		WithMethod(http.MethodPost).
 		WithBody(bytes.NewBufferString(params.Encode())).
 		SetHeader("Content-Type", "application/x-www-form-urlencoded").
 		Do().

providers/logingov.go

@@ -8,6 +8,7 @@ import (
 	"errors"
 	"fmt"
 	"math/big"
+	"net/http"
 	"net/url"
 	"os"
 	"time"
@@ -237,7 +238,7 @@ func (p *LoginGovProvider) Redeem(ctx context.Context, _, code, codeVerifier str
 	}
 	err = requests.New(p.RedeemURL.String()).
 		WithContext(ctx).
-		WithMethod("POST").
+		WithMethod(http.MethodPost).
 		WithBody(bytes.NewBufferString(params.Encode())).
 		SetHeader("Content-Type", "application/x-www-form-urlencoded").
 		Do().

providers/ms_entra_id.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"net/http"
 	"net/url"
 	"os"
 	"regexp"
@@ -304,7 +305,7 @@ func (p *MicrosoftEntraIDProvider) checkTenantMatchesTenantList(tenant string, a
 func (p *MicrosoftEntraIDProvider) fetchToken(ctx context.Context, params url.Values) (*oauth2.Token, error) {
 	resp := requests.New(p.RedeemURL.String()).
 		WithContext(ctx).
-		WithMethod("POST").
+		WithMethod(http.MethodPost).
 		WithBody(bytes.NewBufferString(params.Encode())).
 		SetHeader("Content-Type", "application/x-www-form-urlencoded").
 		Do()

providers/provider_default.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"net/http"
 	"net/url"
 
 	"github.com/oauth2-proxy/oauth2-proxy/v7/pkg/apis/middleware"
@@ -71,7 +72,7 @@ func (p *ProviderData) Redeem(ctx context.Context, redirectURL, code, codeVerifi
 
 	result := requests.New(p.RedeemURL.String()).
 		WithContext(ctx).
-		WithMethod("POST").
+		WithMethod(http.MethodPost).
 		WithBody(bytes.NewBufferString(params.Encode())).
 		SetHeader("Content-Type", "application/x-www-form-urlencoded").
 		Do()

providers/srht.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
+	"net/http"
 	"net/url"
 
 	"github.com/oauth2-proxy/oauth2-proxy/v7/pkg/apis/sessions"
@@ -75,7 +76,7 @@ func NewSourceHutProvider(p *ProviderData) *SourceHutProvider {
 func (p *SourceHutProvider) EnrichSession(ctx context.Context, s *sessions.SessionState) error {
 	json, err := requests.New(p.ProfileURL.String()).
 		WithContext(ctx).
-		WithMethod("POST").
+		WithMethod(http.MethodPost).
 		SetHeader("Content-Type", "application/json").
 		SetHeader("Authorization", "Bearer "+s.AccessToken).
 		WithBody(bytes.NewBufferString(`{"query": "{ me { username, email } }"}`)).