Bump pyelftools from 0.26 to 0.27 in /docker/build_scripts (#818)

Bumps [pyelftools](https://github.com/eliben/pyelftools) from 0.26 to 0.27.
- [Release notes](https://github.com/eliben/pyelftools/releases)
- [Changelog](https://github.com/eliben/pyelftools/blob/master/CHANGES)
- [Commits](eliben/pyelftools@v0.26...v0.27)

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

docker/build_scripts/requirements-tools.txt

@@ -6,8 +6,9 @@ certifi==2020.6.20 \
 auditwheel==3.2.0 \
     --hash=sha256:374a42f5ed95aea02ce9e775bbc4abdf57e84054400bab063616f0ab9bb20ebe
 # these packages required for auditwheel
-pyelftools==0.26 \
-    --hash=sha256:cc0ea0de82b240a73ef4056fce44acbb4727dca7d66759371aff2bad457ed711
+pyelftools==0.27 \
+    --hash=sha256:5609aa6da1123fccfae2e8431a67b4146aa7fad5b3889f808df12b110f230937 \
+    --hash=sha256:cde854e662774c5457d688ca41615f6594187ba7067af101232df889a6b7a66b
 wheel==0.34.2 \
     --hash=sha256:df277cb51e61359aba502208d680f90c0493adec6f0e848af94948778aed386e \
     --hash=sha256:8788e9155fe14f54164c1b9eb0a319d98ef02c160725587ad60f14ddc57b6f96