異常Canonical names should be kebab-case('-'separated)、lower

異常Canonical names should be kebab-case('-'separated)、lowercase alpha-numeric characters and must start with a letter

Description:

Configuration property name 'projectUrl' is not valid:

    Invalid characters: 'U'
    Bean: projectUrlConfig
    Reason: Canonical names should be kebab-case ('-' separated), lowercase alpha-numeric characters and must start with a letter

Action:

Modify 'projectUrl' so that it conforms to the canonical names requirements.

Canonical names should be kebab-case ('-' separated), lowercase alpha-numeric characters and must start with a letter
仕様名はkebab大文字と小文字(「-」で区切る)、小文字と数字の文字で、アルファベットで始まる必要があります.
SpringBoot公式ドキュメント参照

Relaxed Binding

Spring Boot uses some relaxed rules for binding Environment properties to @ConfigurationProperties beans, so there does not need to be an exact match between the Environment property name and the bean property name. Common examples where this is useful include dash-separated environment properties (for example, context-path binds to contextPath), and capitalized environment properties (for example, PORT binds to port).

 
Spring Boot Environment @ConfigurationProperties bean， Environment bean 。  （ ，context-path contextPath） （ ，PORT ）。

ProjectUrlをproject-urlに変更する