[8.12] [Fleet] Fix wrong policy_id in dev tools flyout request (#176729) (#176800)

# Backport

This will backport the following commits from `main` to `8.12`:
- [[Fleet] Fix wrong policy_id in dev tools flyout request
(#176729)](https://github.com/elastic/kibana/pull/176729)

<!--- Backport version: 9.4.3 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sqren/backport)

<!--BACKPORT [{"author":{"name":"Cristina
Amico","email":"criamico@users.noreply.github.com"},"sourceCommit":{"committedDate":"2024-02-13T10:02:20Z","message":"[Fleet]
Fix wrong policy_id in dev tools flyout request (#176729)\n\nFixes
https://github.com/elastic/kibana/issues/172798\r\n\r\n##
Summary\r\nSmall bug fix: when adding a new integration, the `policy_id`
in dev\r\ntools flyout request was not correct\r\n\r\nSteps to
reproduce:\r\n\r\n- Add one agent policy to the stack\r\n- Go to any
integration and navigate to `add integration` page\r\n- Switch to
`Existing hosts` and select an existing policy. \r\n- Open `Preview API
request`. The policy id in the preview should be the\r\none from the
selected policy\r\n- Switch back to `New hosts`\r\n- Open `Preview API
request`. The policy id should be\r\n`<agent_policy_id>` again (not the
one from the previously selected\r\npolicy)\r\n\r\n![Screenshot
2024-02-12 at 17
56\r\n45](6f2e5085-7418-4fef-ac4e-79b57d551722)","sha":"466a05ae843f3aeefaa035121dbb9e642bd0eed6","branchLabelMapping":{"^v8.13.0$":"main","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["release_note:skip","Team:Fleet","backport:prev-minor","v8.13.0"],"title":"[Fleet]
Fix wrong policy_id in dev tools flyout
request","number":176729,"url":"https://github.com/elastic/kibana/pull/176729","mergeCommit":{"message":"[Fleet]
Fix wrong policy_id in dev tools flyout request (#176729)\n\nFixes
https://github.com/elastic/kibana/issues/172798\r\n\r\n##
Summary\r\nSmall bug fix: when adding a new integration, the `policy_id`
in dev\r\ntools flyout request was not correct\r\n\r\nSteps to
reproduce:\r\n\r\n- Add one agent policy to the stack\r\n- Go to any
integration and navigate to `add integration` page\r\n- Switch to
`Existing hosts` and select an existing policy. \r\n- Open `Preview API
request`. The policy id in the preview should be the\r\none from the
selected policy\r\n- Switch back to `New hosts`\r\n- Open `Preview API
request`. The policy id should be\r\n`<agent_policy_id>` again (not the
one from the previously selected\r\npolicy)\r\n\r\n![Screenshot
2024-02-12 at 17
56\r\n45](6f2e5085-7418-4fef-ac4e-79b57d551722)","sha":"466a05ae843f3aeefaa035121dbb9e642bd0eed6"}},"sourceBranch":"main","suggestedTargetBranches":[],"targetPullRequestStates":[{"branch":"main","label":"v8.13.0","branchLabelMappingKey":"^v8.13.0$","isSourceBranch":true,"state":"MERGED","url":"https://github.com/elastic/kibana/pull/176729","number":176729,"mergeCommit":{"message":"[Fleet]
Fix wrong policy_id in dev tools flyout request (#176729)\n\nFixes
https://github.com/elastic/kibana/issues/172798\r\n\r\n##
Summary\r\nSmall bug fix: when adding a new integration, the `policy_id`
in dev\r\ntools flyout request was not correct\r\n\r\nSteps to
reproduce:\r\n\r\n- Add one agent policy to the stack\r\n- Go to any
integration and navigate to `add integration` page\r\n- Switch to
`Existing hosts` and select an existing policy. \r\n- Open `Preview API
request`. The policy id in the preview should be the\r\none from the
selected policy\r\n- Switch back to `New hosts`\r\n- Open `Preview API
request`. The policy id should be\r\n`<agent_policy_id>` again (not the
one from the previously selected\r\npolicy)\r\n\r\n![Screenshot
2024-02-12 at 17
56\r\n45](6f2e5085-7418-4fef-ac4e-79b57d551722)","sha":"466a05ae843f3aeefaa035121dbb9e642bd0eed6"}}]}]
BACKPORT-->

Co-authored-by: Cristina Amico <criamico@users.noreply.github.com>

x-pack/plugins/fleet/public/applications/fleet/sections/agent_policy/create_package_policy_page/single_page_layout/hooks/devtools_request.tsx

@@ -48,7 +48,7 @@ export function useDevToolsRequest({
           newAgentPolicy,
           withSysMonitoring && !packagePolicyIsSystem
         )}\n\n${generateCreatePackagePolicyDevToolsRequest({
-          ...packagePolicy,
+          ...{ ...packagePolicy, policy_id: '' },
         })}`,
         i18n.translate(
           'xpack.fleet.createPackagePolicy.devtoolsRequestWithAgentPolicyDescription',