Fixed font for Heading Issue #8971 (#9358)

<!-- Clearly explain the need for these changes: -->
- Changed the Font weight to semibold.
- Adjusted size to 48px.
- Fixed line-height to 54px.
### Changes 🏗️

<!-- Concisely describe all of the changes made in this pull request:
-->

### Checklist 📋

#### For code changes:
- [ ] I have clearly listed my changes in the PR description
- [ ] I have made a test plan
- [ ] I have tested my changes according to the test plan:
  <!-- Put your test plan here: -->
  - [ ] ...

<details>
  <summary>Example test plan</summary>
  
  - [ ] Create from scratch and execute an agent with at least 3 blocks
- [ ] Import an agent from file upload, and confirm it executes
correctly
  - [ ] Upload agent to marketplace
- [ ] Import an agent from marketplace and confirm it executes correctly
  - [ ] Edit an agent from monitor, and confirm it executes correctly
</details>

#### For configuration changes:
- [ ] `.env.example` is updated or already compatible with my changes
- [ ] `docker-compose.yml` is updated or already compatible with my
changes
- [ ] I have included a list of my configuration changes in the PR
description (under **Changes**)

<details>
  <summary>Examples of configuration changes</summary>

  - Changing ports
  - Adding new services that need to communicate with each other
  - Secrets or environment variable changes
  - New or infrastructure changes such as databases
</details>

---------

Co-authored-by: Muhammad Safi <muhammadsafi@Muhammads-MacBook-Pro.local>
Co-authored-by: Aarushi <50577581+aarushik93@users.noreply.github.com>

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

@@ -16,24 +16,24 @@ export const HeroSection: React.FC = () => {
   return (
     <div className="mb-2 mt-8 flex flex-col items-center justify-center px-4 sm:mb-4 sm:mt-12 sm:px-6 md:mb-6 md:mt-16 lg:my-24 lg:px-8 xl:my-16">
       <div className="w-full max-w-3xl lg:max-w-4xl xl:max-w-5xl">
-        <div className="8md:mb-8 mb-4 text-center">
+        <div className="mb-4 text-center md:mb-8">
           <h1 className="text-center">
-            <span className="font-poppins text-5xl font-semibold leading-[54px] text-neutral-950 dark:text-neutral-50">
+            <span className="font-poppin text-[48px] font-semibold leading-[54px] text-neutral-950 dark:text-neutral-50">
               Explore AI agents built for{" "}
             </span>
-            <span className="font-poppins text-5xl font-semibold leading-[54px] text-violet-600">
+            <span className="font-poppin text-[48px] font-semibold leading-[54px] text-violet-600">
               you
             </span>
             <br />
-            <span className="font-poppins text-5xl font-semibold leading-[54px] text-neutral-950 dark:text-neutral-50">
+            <span className="font-poppin text-[48px] font-semibold leading-[54px] text-neutral-950 dark:text-neutral-50">
               by the{" "}
             </span>
-            <span className="font-poppins text-5xl font-semibold leading-[54px] text-blue-500">
+            <span className="font-poppin text-[48px] font-semibold leading-[54px] text-blue-500">
               community
             </span>
           </h1>
         </div>
-        <h3 className="mb:text-2xl font-geist mb-6 text-center text-xl font-normal leading-loose text-neutral-700 dark:text-neutral-300 md:mb-12">
+        <h3 className="mb:text-2xl mb-6 text-center font-sans text-xl font-normal leading-loose text-neutral-700 dark:text-neutral-300 md:mb-12">
           Bringing you AI agents designed by thinkers from around the world
         </h3>
         <div className="mb-4 flex justify-center sm:mb-5 md:mb-6">