deps: follow openkal 0.7.0

规范新增 `openkal.random`(mcpplibs/openkal#8),版本升到 0.7.0。

⚠️ CI 有一道版本同步门,而它的诊断说明了为什么必须一起改:

    this is openkal 0.7.0 and this implementation is written against
    openkal 0.6.0. Nothing is wrong with either; they are not in step.

⭐ 本包**不提供** `openkal.random`,而那不是偏离 —— 6.1 条规定实现提供一个
接口是全有或全无,不提供的接口作为链接期定义缺席。这里跟随的只是规范版本,
不是接口集合。

Author: Sunrisepeak

mcpp.toml

@@ -33,7 +33,7 @@ repo        = "https://github.com/mcpplibs/openkal-opensbi"
 # The contract, not an implementation of it. Declaring it turns a version
 # mismatch into a resolution-time message rather than a link-time one.
 [dependencies]
-openkal = "0.6.0"
+openkal = "0.7.0"
 
 # ⭐ WHAT RECEIVES CONTROL, WHICH IS A STATEMENT ABOUT THE PROGRAM.
 #