update walkthrough about creating projects

[Eskibear]

Changes:

• Use "Spring Initilizr" instead of "Spring" to locate the create project command, otherwise there would be lots of other Spring related commands on the list.
• remove "in VS Code" and duplicate "Spring Boot" for simplicity, as the section is all about that, which should be safe and won't cause confusion.

[Eskibear]

Spring Initializr as keyword:

Spring as keyword: (Focus on other commands section, as new users won't have recently used commands)

• Spring App: is from Azure Spring Apps extension.
• Spring Boot: and Spring Boot Dashboard: are also on the top due to alphabetical order.

[martinlippert]

Makes a lot of sense. Thanks @Eskibear for the contribution!!!