Fix spelling mistake (#4265)

* Fix misspell.

* Add missing link title.

src/data/roadmaps/software-design-architecture/content/107-architectural-patterns/101-soa.md

@@ -1,6 +1,6 @@
 # SOA
 
-SOA (Service-Oriented Architecture) is an architectural pattern that is used to design and organize software systems as a collection of services that can be accessed over a network, these services are autonomous, self-contained units of functionality that can be reused and combined to create new functionality. SOA services are designed to be loosely coupled, meaning that they do not depend on the implementation details of other services, they communicate with each other through well-defined interfaces, usually using a protocol such as HTTP or SOAP. SOA provides several advantages over other architectural patterns, such as reusability, modularity, interoperability, and scalability. It can be implemented using a variety of technologies, such as Web Services, REST, and microservices.s
+SOA (Service-Oriented Architecture) is an architectural pattern that is used to design and organize software systems as a collection of services that can be accessed over a network, these services are autonomous, self-contained units of functionality that can be reused and combined to create new functionality. SOA services are designed to be loosely coupled, meaning that they do not depend on the implementation details of other services, they communicate with each other through well-defined interfaces, usually using a protocol such as HTTP or SOAP. SOA provides several advantages over other architectural patterns, such as reusability, modularity, interoperability, and scalability. It can be implemented using a variety of technologies, such as Web Services, REST, and microservices.
 
 Learn more from the following links:
 

src/data/roadmaps/software-design-architecture/content/107-architectural-patterns/105-blackboard-pattern.md

@@ -5,4 +5,4 @@ The Blackboard architectural pattern is a software design pattern that allows fo
 Learn more from the following links:
 
 - [Overview of Blackboard (design pattern)](<https://en.wikipedia.org/wiki/Blackboard_(design_pattern)>)
-- [](http://www.openloop.com/softwareEngineering/patterns/architecturePattern/arch_Blackboard.htm)
+- [Architectural Patterns: Blackboard](http://www.openloop.com/softwareEngineering/patterns/architecturePattern/arch_Blackboard.htm)