Bump datatables.net-fixedheader-bs4 from 3.1.7 to 3.1.8 (#3385)

Bumps [datatables.net-fixedheader-bs4](https://datatables.net) from 3.1.7 to 3.1.8.

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -88,7 +88,7 @@
     "datatables.net-buttons-bs4": "^1.6.5",
     "datatables.net-colreorder-bs4": "^1.5.3",
     "datatables.net-fixedcolumns-bs4": "^3.3.2",
-    "datatables.net-fixedheader-bs4": "^3.1.7",
+    "datatables.net-fixedheader-bs4": "^3.1.8",
     "datatables.net-keytable-bs4": "^2.5.3",
     "datatables.net-responsive-bs4": "^2.2.7",
     "datatables.net-rowgroup-bs4": "^1.1.2",