[18.0][MIG] web_assets_warmup: Migration to 18.0

[xaviedoanhduy]

Note

• Since Odoo v17.0, assets are no longer generated in the same transaction that generates a report. They are now generated when retrieved, through the /web/assets route. See [FW][REF] generate assets bundle outside t-call-assets odoo/odoo#140124
• As a consequence, the problematic case that led to the creation of web_assets_warmup can no longer occur: [14.0][ADD] web_assets_warmup #2614 (comment)
• That said, module still has some value in "warming" up common assets for reports
• Since 16.0, odoo introduced a more generic env['ir.qweb']._pregenerate_assets_bundles(), but used for tests only, see [IMP] speedup /web (and other page) loading odoo/odoo#99176
• commit_assetsbundle was removed when rendering the report in commit: odoo/odoo@ad4deba
• "declare assets in manifest, not in xml" so this commit changed xmlid parameter to bundles, see in: odoo/odoo@8cc06617
• web.assets_common was removed in commit odoo/odoo@02cba88d3

I also conducted some speed tests when printing the report for the first time (checked when calling the _render_qweb_pdf method)(ref)

• when installing the sale_management module, and not installing web_assets_warmup: 3.861 (s)
  

• when installing the sale_management and web_assets_warmup modules but not manually executing the schedule action task (Generate report assets): 3.949 (s)
  

• when installing the sale_management and web_assets_warmup modules then manually executing the schedule action task (Generate report assets): 2.860 (s)