feat: support HttpClient client integration (#504)

Author: rchl

docs/content/en/sentry/options.md

@@ -237,7 +237,7 @@ Note that the module sets the following defaults when publishing is enabled:
   }
   ```
 - Sentry by default also enables the following browser integrations: `InboundFilters`, `FunctionToString`, `TryCatch`, `Breadcrumbs`, `GlobalHandlers`, `LinkedErrors`, `Dedupe`, `HttpContext`.
-- The full list of client integrations that are supported: `Breadcrumbs`, `CaptureConsole`, `Debug`, `Dedupe`, `ExtraErrorData`, `FunctionToString`, `GlobalHandlers`, `HttpContext`, `InboundFilters`, `LinkedErrors`, `ReportingObserver`, `RewriteFrames`, `TryCatch`.
+- The full list of client integrations that are supported: `Breadcrumbs`, `CaptureConsole`, `Debug`, `Dedupe`, `ExtraErrorData`, `FunctionToString`, `GlobalHandlers`, `HttpClient`, `HttpContext`, `InboundFilters`, `LinkedErrors`, `ReportingObserver`, `RewriteFrames`, `TryCatch`.
 - Integration options can be specified in the object value corresponding to the individual integration key.
 - To disable integration that is enabled by default, pass `false` as a value. For example to disable `ExtraErrorData` integration (only), set the option to:
   ```js

lib/core/options.js

@@ -2,7 +2,7 @@ import merge from 'lodash.mergewith'
 import * as Integrations from '@sentry/integrations'
 import { canInitialize } from './utils'
 
-export const PLUGGABLE_INTEGRATIONS = ['CaptureConsole', 'Debug', 'Dedupe', 'ExtraErrorData', 'ReportingObserver', 'RewriteFrames']
+export const PLUGGABLE_INTEGRATIONS = ['CaptureConsole', 'Debug', 'Dedupe', 'ExtraErrorData', 'HttpClient', 'ReportingObserver', 'RewriteFrames']
 export const BROWSER_INTEGRATIONS = ['InboundFilters', 'FunctionToString', 'TryCatch', 'Breadcrumbs', 'GlobalHandlers', 'LinkedErrors', 'HttpContext']
 const SERVER_INTEGRATIONS = ['CaptureConsole', 'Debug', 'Dedupe', 'ExtraErrorData', 'RewriteFrames', 'Modules', 'Transaction']