doc: format v8.md in preparation for stricter linting

PR-URL: #40647
Reviewed-By: Antoine du Hamel <[email protected]>
Reviewed-By: Michaël Zasso <[email protected]>

Author: Trott

doc/api/v8.md

@@ -627,6 +627,7 @@ stopHookSet();
 ```
 
 ### `promiseHooks.onInit(init)`
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@@ -650,6 +651,7 @@ const stop = promiseHooks.onInit((promise, parent) => {});
 ```
 
 ### `promiseHooks.onSettled(settled)`
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@@ -674,6 +676,7 @@ const stop = promiseHooks.onSettled((promise) => {});
 ```
 
 ### `promiseHooks.onBefore(before)`
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@@ -698,6 +701,7 @@ const stop = promiseHooks.onBefore((promise) => {});
 ```
 
 ### `promiseHooks.onAfter(after)`
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@@ -722,6 +726,7 @@ const stop = promiseHooks.onAfter((promise) => {});
 ```
 
 ### `promiseHooks.createHook(callbacks)`
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@@ -778,7 +783,7 @@ not necessarily ever even be garbage collected.
 
 Because promises are asynchronous resources whose lifecycle is tracked
 via the promise hooks mechanism, the `init()`, `before()`, `after()`, and
-`settled()` callbacks *must not* be async functions as they create more
+`settled()` callbacks _must not_ be async functions as they create more
 promises which would produce an infinite loop.
 
 While this API is used to feed promise events into [`async_hooks`][], the