fix: [Integrations > Install integration only][KEYBOARD]: Tooltips mu…

…st be keyboard accessible (#180174)

Closes: elastic/security-team#8982

## Description

The [axe browser plugin](https://deque.com/axe) is reporting some
scrollable regions are not keyboard accessible. This isn't happening in
all integrations, but did happen in the Amazon DynamoDB, so I'll use
that as my example. Screenshot below.

### Steps to recreate

1. Create a new Security Serverless project if none exist
2. When the project is ready, open it and go to Integrations, under the
Project Settings in the lower left navigation
3. Search for DynamoDB in the Integrations, and click on the card
4. Click "Add Amazon DynamoDB" to load the prompt page
5. Click "Add integration only (skip agent installation)"
6. Tab through the first few form fields, and verify you cannot expand
the tooltips without hovering them

### What was done?:

1. `EuiToolTip` was replaced to `EuiIconTip`


### Screens

<img width="534" alt="image"
src="https://github.com/elastic/kibana/assets/20072247/5c5ad873-0c79-4fed-94b1-5dd614bbe6b3">

x-pack/plugins/fleet/public/applications/fleet/sections/agent_policy/create_package_policy_page/components/steps/components/package_policy_input_var_field.tsx

@@ -24,8 +24,7 @@ import {
   EuiFlexItem,
   EuiButtonEmpty,
   EuiLink,
-  EuiToolTip,
-  EuiIcon,
+  EuiIconTip,
 } from '@elastic/eui';
 import styled from 'styled-components';
 
@@ -344,16 +343,16 @@ const SecretFieldLabel = ({ fieldLabel }: { fieldLabel: string }) => {
           {fieldLabel}
         </EuiFlexItem>
         <EuiFlexItem grow={false}>
-          <EuiToolTip
+          <EuiIconTip
+            type="iInCircle"
+            position="top"
             content={
               <FormattedMessage
                 id="xpack.fleet.createPackagePolicy.stepConfigure.secretLearnMorePopoverContent"
                 defaultMessage="This value is a secret. After you save this integration policy, you won't be able to view the value again."
               />
             }
-          >
-            <EuiIcon aria-label="Secret value" type="questionInCircle" color="subdued" />
-          </EuiToolTip>
+          />
         </EuiFlexItem>
       </EuiFlexGroup>