feat(sentry apps): Update the refresh token docs to have manual refresh (#15390)

Author: Christinarlong

docs/organization/integrations/integration-platform/public-integration.mdx

@@ -66,7 +66,7 @@ All public integrations can be installed via a fixed external url: `https://sent
 Public integrations generate [authentication tokens](/organization/integrations/integration-platform/#auth-tokens) after a successful [OAuth installation](#oauth-process).
 These tokens automatically expire every eight hours, meaning they must be refreshed manually.
 
-### Refreshing Tokens
+### Refreshing Tokens via Refresh Token (preferred)
 
 In the initial installation, you'll need the grant code given to you in either the installation webhook request or the redirect URL, in addition to your integration's client ID and client Secret:
 
@@ -108,6 +108,50 @@ def refresh_token(install_id):
     return new_token
 ```
 
+### Refreshing Tokens Manually for Integrators
+Sometimes technical anomalies can lead to token refreshing being committed on the Sentry side but then the token is lost in transmission on the way back. As a result, we've added a method for integrators to explicitly refresh and request a new token for their installers.
+
+This manual refresh method uses a different authorization scheme where you will need to send a JWT signed with your client secret to the previous
+`/api/0/sentry-app-installations/{}/authorizations/` endpoint with the below claims and payload.
+
+```python
+def manual_token_refresh(install_id):
+    url = u'https://sentry.io/api/0/sentry-app-installations/{}/authorizations/'
+    url = url.format(install_id)
+    
+    now = datetime.now(timezone.utc).timestamp()
+    client_secret = "XXXX-XXXX-XXXX"
+    client_id = "1234-5678-9999"
+    iat = now
+    exp = now + 60 # 1 minute validity period
+    
+    claims = {
+		    'iss': client_id,
+		    'sub': client_id,
+		    'iat': iat,
+		    'exp': exp,
+		    'jti': str(uuid.uuid4()),
+    }
+    jwt_token = jwt.encode(claims, client_secret, algorithm="HS256")
+    
+    headers = {
+            'Authorization': f'Bearer {jwt_token}',
+            'Content-Type': 'application/json'
+    }
+    payload = {
+        'grant_type': 'urn:sentry:params:oauth:grant-type:jwt-bearer',
+    }
+    
+	resp = requests.post(url, json=payload, headers=headers) 
+    data = resp.json()
+
+    new_token = data['token']
+    new_refresh_token = data['refreshToken']
+    # ... Securely update the token and refresh_token in DB...
+
+    return new_token
+```
+
 The data you can expect back for both the initial grant code exchange and subsequent token refreshes is as follows:
 
 ```json