docs: fixed some typos, formatting, grammar (#11540)

# Which Problems Are Solved

- Typos
- Punctuation
- Markdown table formatting
- ...

(A bunch of issues my editor gave)

# How the Problems Are Solved


# Additional Changes


# Additional Context

backend/v3/storage/database/migration.go

@@ -3,7 +3,7 @@ package database
 import "context"
 
 type Migrator interface {
-	// Migrate executes migrations to setup the database.
+	// Migrate executes migrations to set up the database.
 	// The method can be called once per running Zitadel.
 	Migrate(ctx context.Context) error
 }

backend/v3/storage/database/order.go

@@ -1,7 +1,7 @@
 package database
 
 // Order represents a SQL condition.
-// Its written after the ORDER BY keyword in a SQL statement.
+// It's written after the ORDER BY keyword in a SQL statement.
 type Order interface {
 	Write(builder *StatementBuilder)
 }