chore: panic if a random name cannot be created (#853)

If that happens so much will go wrong that there is no point in continuing to do anything. It simplifies the requirements of the caller: it may be a function that is assumed to never error.

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  - [PR](https://code.forgejo.org/forgejo/runner/pulls/853): <!--number 853 --><!--line 0 --><!--description Y2hvcmU6IHBhbmljIGlmIGEgcmFuZG9tIG5hbWUgY2Fubm90IGJlIGNyZWF0ZWQ=-->chore: panic if a random name cannot be created<!--description-->
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Reviewed-on: https://code.forgejo.org/forgejo/runner/pulls/853
Reviewed-by: Mathieu Fenniak <mfenniak@noreply.code.forgejo.org>
Co-authored-by: Earl Warren <contact@earl-warren.org>
Co-committed-by: Earl Warren <contact@earl-warren.org>

act/common/randname.go

@@ -5,12 +5,21 @@ package common
 import (
 	"crypto/rand"
 	"encoding/hex"
+	"fmt"
 )
 
-func RandName(size int) (string, error) {
+func randName(size int) (string, error) {
 	randBytes := make([]byte, size)
 	if _, err := rand.Read(randBytes); err != nil {
 		return "", err
 	}
 	return hex.EncodeToString(randBytes), nil
 }
+
+func MustRandName(size int) string {
+	name, err := randName(size)
+	if err != nil {
+		panic(fmt.Errorf("RandName(%d): %v", size, err))
+	}
+	return name
+}