Replace fake tokens with a placeholder

doc/api/freeze_periods.md

@@ -31,7 +31,7 @@ GET /projects/:id/freeze_periods
 Example request:
 
 ```shell
-curl --header "PRIVATE-TOKEN: gVWYVHDRzXiRpN1rUC8T" "https://gitlab.example.com/api/v4/projects/19/freeze_periods"
+curl --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects/19/freeze_periods"
 ```
 
 Example response:
@@ -65,7 +65,7 @@ GET /projects/:id/freeze_periods/:freeze_period_id
 Example request:
 
 ```shell
-curl --header "PRIVATE-TOKEN: gVWYVHDRzXiRpN1rUC8T" "https://gitlab.example.com/api/v4/projects/19/freeze_periods/1"
+curl --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects/19/freeze_periods/1"
 ```
 
 Example response:
@@ -99,7 +99,7 @@ POST /projects/:id/freeze_periods
 Example request:
 
 ```shell
-curl --header 'Content-Type: application/json' --header "PRIVATE-TOKEN: gVWYVHDRzXiRpN1rUC8T" \
+curl --header 'Content-Type: application/json' --header "PRIVATE-TOKEN: <your_access_token>" \
      --data '{ "freeze_start": "0 23 * * 5", "freeze_end": "0 7 * * 1", "cron_timezone": "UTC" }' \
      --request POST https://gitlab.example.com/api/v4/projects/19/freeze_periods
 ```
@@ -136,7 +136,7 @@ PUT /projects/:id/freeze_periods/:tag_name
 Example request:
 
 ```shell
-curl --header 'Content-Type: application/json' --header "PRIVATE-TOKEN: gVWYVHDRzXiRpN1rUC8T" \
+curl --header 'Content-Type: application/json' --header "PRIVATE-TOKEN: <your_access_token>" \
      --data '{ "freeze_end": "0 8 * * 1" }' \
      --request PUT https://gitlab.example.com/api/v4/projects/19/freeze_periods/1
 ```
@@ -170,6 +170,6 @@ DELETE /projects/:id/freeze_periods/:freeze_period_id
 Example request:
 
 ```shell
-curl --request DELETE --header "PRIVATE-TOKEN: gVWYVHDRzXiRpN1rUC8T" "https://gitlab.example.com/api/v4/projects/19/freeze_periods/1"
+curl --request DELETE --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects/19/freeze_periods/1"
 
 ```