Delete ISSUE_TEMPLATE.md

.github/ISSUE_TEMPLATE.md

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-
-**Description**
-
-<!--
-Briefly describe the problem you are having in a few paragraphs.
--->
-
-**Steps to reproduce the issue:**
-1.
-2.
-3.
-
-**Describe the results you received:**
-
-**Describe the results you expected:**
-
-**Output of `go version`:**
-
-```text
-(paste your output here)
-```
-
-**Excelize version or commit ID:**
-
-```text
-(paste here)
-```
-
-**Environment details (OS, Microsoft Excel™ version, physical, etc.):**