[PATCH] dpkg-source: lock isar-apt while do_fetch_common_source

[Uladzimir Bely <ubely@ilbers.de>]

Task do_fetch_common_source requires isar-apt repo unchanged while
running "apt-get ... source ..." inside. Otherwise, it may fail on repo
"Sources" or "Packages" file:

```
Err:4 file:/isar-apt isar/main Sources
  Hash Sum mismatch
```
This is quite often reproduced in CI since commit 2ca3a7e.

Signed-off-by: Uladzimir Bely <ubely@ilbers.de>
---
 meta/classes/dpkg-source.bbclass | 1 +
 1 file changed, 1 insertion(+)

diff --git a/meta/classes/dpkg-source.bbclass b/meta/classes/dpkg-source.bbclass
index d6ab5aad..a70a392d 100644
--- a/meta/classes/dpkg-source.bbclass
+++ b/meta/classes/dpkg-source.bbclass
@@ -41,6 +41,7 @@ do_dpkg_build[depends] += "${BPN}:do_deploy_source"
 SCHROOT_MOUNTS = "${WORKDIR}:/work ${REPO_ISAR_DIR}/${DISTRO}:/isar-apt"
 
 do_fetch_common_source[depends] += "${SCHROOT_DEP} ${BPN}:do_deploy_source"
+do_fetch_common_source[lockfiles] = "${REPO_ISAR_DIR}/isar.lock"
 do_fetch_common_source[network] = "${TASK_USE_SUDO}"
 do_fetch_common_source() {
     schroot_create_configs
-- 
2.44.2