Add remove_last, replace_last documentation (#1805)

_filters/remove_last.md

@@ -0,0 +1,19 @@
+---
+title: remove_last
+description: Liquid filter that removes the last occurence of a given substring from a string.
+version-badge: 5.2.0
+---
+
+Removes only the last occurrence of the specified substring from a string.
+
+<p class="code-label">Input</p>
+```liquid
+{%- raw -%}
+{{ "I strained to see the train through the rain" | remove_last: "rain" }}
+{% endraw %}
+```
+
+<p class="code-label">Output</p>
+```text
+I strained to see the train through the
+```

_filters/replace_last.md

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+---
+title: replace_last
+description: Liquid filter that replaces the last occurrence of a given substring in a string.
+version-badge: 5.2.0
+---
+
+Replaces only the last occurrence of the first argument in a string with the second argument.
+
+<p class="code-label">Input</p>
+```liquid
+{%- raw -%}
+{{ "Take my protein pills and put my helmet on" | replace_last: "my", "your" }}
+{% endraw %}
+```
+
+<p class="code-label">Output</p>
+```text
+Take my protein pills and put your helmet on
+```