Backport doc change from latest upstream merge

See https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/2906Signed-off-by: Rémy Coutable <remy@rymai.me>

doc/user/project/repository/gpg_signed_commits/index.md

@@ -113,25 +113,25 @@ started:
 1. Use the following command to list the private GPG key you just created:
 
     ```
-    gpg --list-secret-keys --keyid-format 0xLONG mr@robot.sh
+    gpg --list-secret-keys --keyid-format LONG mr@robot.sh
     ```
 
     Replace `mr@robot.sh` with the email address you entered above.
 
 1. Copy the GPG key ID that starts with `sec`. In the following example, that's
-   `0x30F2B65B9246B6CA`:
+   `30F2B65B9246B6CA`:
 
     ```
-    sec   rsa4096/0x30F2B65B9246B6CA 2017-08-18 [SC]
+    sec   rsa4096/30F2B65B9246B6CA 2017-08-18 [SC]
           D5E4F29F3275DC0CDA8FFC8730F2B65B9246B6CA
     uid                   [ultimate] Mr. Robot <mr@robot.sh>
-    ssb   rsa4096/0xB7ABC0813E4028C0 2017-08-18 [E]
+    ssb   rsa4096/B7ABC0813E4028C0 2017-08-18 [E]
     ```
 
 1. Export the public key of that ID (replace your key ID from the previous step):
 
     ```
-    gpg --armor --export 0x30F2B65B9246B6CA
+    gpg --armor --export 30F2B65B9246B6CA
     ```
 
 1. Finally, copy the public key and [add it in your profile settings](#adding-a-gpg-key-to-your-account)
@@ -167,28 +167,28 @@ key to use.
 1. Use the following command to list the private GPG key you just created:
 
     ```
-    gpg --list-secret-keys --keyid-format 0xLONG mr@robot.sh
+    gpg --list-secret-keys --keyid-format LONG mr@robot.sh
     ```
 
     Replace `mr@robot.sh` with the email address you entered above.
 
 1. Copy the GPG key ID that starts with `sec`. In the following example, that's
-   `0x30F2B65B9246B6CA`:
+   `30F2B65B9246B6CA`:
 
     ```
-    sec   rsa4096/0x30F2B65B9246B6CA 2017-08-18 [SC]
+    sec   rsa4096/30F2B65B9246B6CA 2017-08-18 [SC]
           D5E4F29F3275DC0CDA8FFC8730F2B65B9246B6CA
     uid                   [ultimate] Mr. Robot <mr@robot.sh>
-    ssb   rsa4096/0xB7ABC0813E4028C0 2017-08-18 [E]
+    ssb   rsa4096/B7ABC0813E4028C0 2017-08-18 [E]
     ```
 
 1. Tell Git to use that key to sign the commits:
 
     ```
-    git config --global user.signingkey 0x30F2B65B9246B6CA
+    git config --global user.signingkey 30F2B65B9246B6CA
     ```
 
-    Replace `0x30F2B65B9246B6CA` with your GPG key ID.
+    Replace `30F2B65B9246B6CA` with your GPG key ID.
 
 ## Signing commits