doc: fix 'which' to 'that' and added comma

doc/contributing/technical-priorities.md

@@ -21,11 +21,11 @@ on October 1st 2022.
 
 _Present in: 2021_
 
-Base HTTP support is a key component of modern cloud-native applications
+Base HTTP support is a key component of modern cloud-native applications,
 and built-in support was part of what made Node.js a success in the first
 10 years. The current implementation is hard to support and a common
 source of vulnerabilities. We must work towards an
-implementation which is easier to support and makes it easier to integrate
+implementation that is easier to support and makes it easier to integrate
 the new HTTP versions (HTTP3, QUIC) and to support efficient
 implementations of different versions concurrently.
 
@@ -96,7 +96,7 @@ supported tools to implement those processes (logging, metrics and tracing).
 This includes support within the Node.js runtime itself (for example
 generating heap dumps, performance metrics, etc.) as well as support for
 applications on top of the runtime. In addition, it is also important to
-clearly document the use cases, problem determination methods and best
+clearly document the use cases, problem determination methods, and best
 practices for those tools.
 
 ## Better multithreaded support