Fixed CI errors

pkgs/http/lib/src/multipart_request.dart

@@ -162,14 +162,14 @@ class MultipartRequest extends BaseRequest {
 
   @override
   String? get cache {
-    if (this._cache != null) {
-      return this._cache;
-    } else
-      return super.cache;
+    if (_cache != null) {
+      return _cache;
+    }
+    return super.cache;
   }
 
   String? _cache;
   set cache(String? cacheType) {
-    this._cache = cacheType!;
+    _cache = cacheType!;
   }
 }

pkgs/http/lib/src/request.dart

@@ -184,14 +184,14 @@ class Request extends BaseRequest {
 
   @override
   String? get cache {
-    if (this._cache != null) {
-      return this._cache;
-    } else
-      return super.cache;
+    if (_cache != null) {
+      return _cache;
+    }
+    return super.cache;
   }
 
   String? _cache;
   set cache(String? cacheType) {
-    this._cache = cacheType!;
+    _cache = cacheType!;
   }
 }

pkgs/http/lib/src/streamed_request.dart

@@ -55,14 +55,14 @@ class StreamedRequest extends BaseRequest {
 
   @override
   String? get cache {
-    if (this._cache != null) {
-      return this._cache;
-    } else
-      return super.cache;
+    if (_cache != null) {
+      return _cache;
+    }
+    return super.cache;
   }
 
   String? _cache;
   set cache(String? cacheType) {
-    this._cache = cacheType!;
+    _cache = cacheType!;
   }
 }

pkgs/http/lib/src/utils.dart

@@ -73,10 +73,10 @@ Stream<T> onDone<T>(Stream<T> stream, void Function() onDone) =>
 ///
 /// For more references, check (Caching types)[https://developer.mozilla.org/en-US/docs/Web/API/Request/cache]
 mixin HttpCacheUtils {
-  static const String defaultType = "default";
-  static const String reloadType = "reload";
-  static const String noStoringType = "no-store";
-  static const String noCachingType = "no-cache";
-  static const String forceCachingType = "force-cache";
-  static const String onlyIfCachedType = "only-if-cached";
+  static const String defaultType = 'default';
+  static const String reloadType = 'reload';
+  static const String noStoringType = 'no-store';
+  static const String noCachingType = 'no-cache';
+  static const String forceCachingType = 'force-cache';
+  static const String onlyIfCachedType = 'only-if-cached';
 }