fix(marketplace): Fix typography of heading in marketplace (#9737)

- fix #8956

### Changes:
- Updated line height from 28px to 36px for improved readability.
- Ensured that all section headings (“Featured agents”, “Top agents”,
“Featured creators”, and “Become a creator”) now have a uniform style.
- Verified that font-poppins is correctly set in the Tailwind config
file and layout.tsx.
- Color changed from #282828 to #262626

### Scope:
- This PR only includes typography-related adjustments.

![Screenshot 2025-04-02 at 5 29
05 PM](https://github.com/user-attachments/assets/e27b0d52-d8c7-4921-ae18-e3f75264e74d)

autogpt_platform/frontend/src/components/agptui/BecomeACreator.tsx

@@ -25,7 +25,7 @@ export const BecomeACreator: React.FC<BecomeACreatorProps> = ({
       <div className="left-0 top-0 h-px w-full bg-gray-200 dark:bg-gray-700" />
 
       {/* Title */}
-      <h2 className="underline-from-font decoration-skip-ink-none mt-[25px] text-left font-poppins text-[18px] font-semibold leading-[28px] text-neutral-800 dark:text-neutral-200">
+      <h2 className="mb-8 text-left font-poppins text-[18px] font-[600] leading-9 text-neutral-800 dark:text-neutral-200">
         {title}
       </h2>
 

autogpt_platform/frontend/src/components/agptui/composite/AgentsSection.tsx

@@ -8,7 +8,6 @@ import {
   CarouselItem,
 } from "@/components/ui/carousel";
 import { useRouter } from "next/navigation";
-import { cn } from "@/lib/utils";
 
 export interface Agent {
   slug: string;
@@ -47,7 +46,7 @@ export const AgentsSection: React.FC<AgentsSectionProps> = ({
   return (
     <div className="flex flex-col items-center justify-center pb-4 lg:pb-8">
       <div className="w-full max-w-[1360px]">
-        <div className="decoration-skip-ink-none mb-8 mt-[25px] text-left font-poppins text-[18px] font-[600] leading-7 text-[#282828] underline-offset-[from-font] dark:text-neutral-200">
+        <div className="mb-8 font-poppins text-[18px] font-[600] leading-9 text-neutral-800 dark:text-neutral-200">
           {sectionTitle}
         </div>
         {!displayedAgents || displayedAgents.length === 0 ? (

autogpt_platform/frontend/src/components/agptui/composite/FeaturedCreators.tsx

@@ -33,7 +33,7 @@ export const FeaturedCreators: React.FC<FeaturedCreatorsProps> = ({
   return (
     <div className="flex w-full flex-col items-center justify-center py-16">
       <div className="w-full max-w-[1360px]">
-        <h2 className="mb-8 font-poppins text-2xl font-semibold leading-7 text-neutral-800 dark:text-neutral-200">
+        <h2 className="mb-8 text-left font-poppins text-[18px] font-[600] leading-9 text-neutral-800 dark:text-neutral-200">
           {title}
         </h2>
 

autogpt_platform/frontend/src/components/agptui/composite/FeaturedSection.tsx

@@ -47,7 +47,7 @@ export const FeaturedSection: React.FC<FeaturedSectionProps> = ({
 
   return (
     <section className="mx-auto w-full max-w-7xl px-4 pb-16">
-      <h2 className="mb-8 font-poppins text-2xl font-semibold leading-7 text-neutral-800 dark:text-neutral-200">
+      <h2 className="mb-8 text-left font-poppins text-[18px] font-[600] leading-9 text-neutral-800 dark:text-neutral-200">
         Featured agents
       </h2>